Stable Time Loop

""One cannot damage history, because history cannot be changed. I went back in time to steal this because history says it disappeared, and history says it disappeared because I went back to steal it. Past, present, future; it's all written in stone, my dear.""

- Warp, Teen Titans, "How Long Is Forever?"

Through Applied Phlebotinum, Functional Magic, or some other means, our heroes travel back to the past. In the past, they wind up being responsible for the very events that underpin their own "present." This creates a chicken-and-egg scenario, in which the looping sequence of events has no clear beginning. The result of breaking the zeroth law of Time Travel: do not cause the event you went back to prevent.

This is also the basic premise of how Time Travel would work, according to Albert Einstein. Simply put, even if it were possible to travel back in time, you would not be able to change any events in the past, because they've already happened. No matter what your intentions, everything that you did would only fulfill the past. The only thing that would change is your perception of the events. (Hm, this somehow explains Hitler's Time Travel Exemption Act.)

This is sometimes referred to as a "time loop" paradox, particularly when a character, object, or piece of information was never originally created, but exists solely because of its own existence. Also known as a "bootstrap paradox," from the classic Heinlein short story, By His Bootstraps. It's also called an "ontological paradox" on The Other Wiki. The classic hypothetical example is to jump into the future, steal some wondrous gadget, come back to the original time, grab the patent on that gadget and start mass-producing them immediately. Eventually, they become so ubiquitous or so common that you, ten, twenty years younger, show up and steal one. If it's the same one you stole before, it's an Object paradox. If it's not, then it's this. The simplest version is the one where the time machine itself is the product of the stable time loop--the character sees a version of himself pop into existence with a time machine, hand it to him, and press the button, only to be whisked into the past where he hands it to his past self and presses the button.

Tricked-Out Time is when you "change" the past on purpose to resemble this. Compare You Already Changed the Past, Wayback Trip, Timey-Wimey Ball, Retroactive Preparation. For the Recursive Fiction variant of this, see Mutually Fictional.

For further discussion of this trope, see Wikipedia.

Since many examples of this trope aren't revealed until late in the story, and the existence of a loop can itself be a Spoiler, consider yourself spoiler-warned.

Importantly, this trope is not to be confused with Groundhog Day Loop.

Anime and Manga

 * In Simoun,
 * In El-Hazard: The Magnificent World, the main character and company are sent to El Hazard by Ifurita. They meet her in El Hazard, but as an enemy who doesn't remember them. After a Heel Face Turn, Ifurita rescues everyone from a time-space distortion weapon, and realizes that she must be caught in it in order to go back in time in order to start everything.
 * Takahashi's Fire Tripper one-shot story (in some ways a dry run for Inuyasha), avoids the trope almost completely. One can trace the time lines of both characters, and they never "loop" themselves. There is one small loop though that leads to a Fridge Logic moment after the show is over.
 * Mendo from Urusei Yatsura traveled to the past to try to prevent himself from acquiring his fear of darkness and cramped spaces, but he got so angry at his younger self that he ended up attacking his younger self and thereby causing his own phobias.
 * In Martian Successor Nadesico,
 * In Tenchi Muyo! in Love!, the criminal Kain attempts to go back in time to kill Tenchi's mother, Achika, so as to prevent Tenchi from ever having been born. Tenchi and company go back in time to stop him, and the climactic showdown forces Achika to utilize her power to the point that she shortens her own lifespan in order to protect her future son, thus causing her premature death that Tenchi had already experienced in the present/future.
 * During the (rather long) Day 1 of the Mahora Fair sub-arc in Mahou Sensei Negima we get to see a Time Loop following Negi's use of it. Negi redoes the same day four times to make sure he has enough time to spend with every student. At various points Negi will run into students he hasn't run into yet because he's not that far in the loop. Setsuna, Asuna, Konoka and Kotaro all go along with Negi at one time or another in this loop. Naturally when Time Travel isn't a neat parlor trick it stops being so stable... or loop like, and quite wibbly-wobbly.
 * In Sailor Moon, Chibi-Usa is able to exist because
 * In Tsubasa Reservoir Chronicle - avoiding spoilers and the five paragraphs of text that it would require to fully explain it- something the main characters do halfway through the story is directly responsible for the creation of the lead female's hometown as we first saw it.
 * Later combined with reincarnation, parallel universes, and cloning to induce an extreme My Own Grampa scenario.
 * Dragon Ball -
 * Episode of Bardock shows that when Goku's father was defeated by Freeza, he was somehow thrown into the past. There he defeats a ancestor of Freeza, who manages to tell his race of the Saiyans and their super forms before dying.
 * In Natsu no Arashi!, Kaya's diary was lost sixty years ago. So, Arashi time-leaps back to 60 years ago, grabs the diary from before it was lost, and brings it to the present. Which, as Hajime immediately explains, is why it went missing in the first place.
 * When the heroes of Rave Master reach what was once the Kingdom of Symphonia they discover, along with the grave of Resha Valentine, a skeleton wearing a necklace identical to one Elie was wearing, complete with engraving, that she had purchased from a store. Many volumes later, characters go back in time.
 * In the Bamboo Rhapsody episode of Suzumiya Haruhi, . When Kyon complains that this contradicts Mikuru's explanation of Time Travel, a sufficiently-advanced Yuki brushes it off with, "since there's no conclusion to the paradox theory, there's no way to prove there's no paradox." The Stable Time Loop gets tied in knots in The Disappearance of Suzumiya Haruhi, where Mikuru is the embodiment of stable time loops anyway; an entire book is dedicated to her walking around with Kyon triggering key events for her future. This phenomenon pisses off the anti-Mikuru, "Sneering Bastard," to no end; he hates that You Can't Fight Fate.
 * In Mx0,
 * During the Great War in Kyo Kara Maoh, Suzanna Julia doesn't fully accept that she's going to die and that her soul is to become the next Maoh. So, to convince her, what does Shinou do? SEND HER YUURI, OF COURSE. Yuuri's presence in the past makes Julia finally accept her fate, and in turn makes it possible for him to exist as Maoh in the future.
 * Yuki Saiko of Silent Moebius has a mysteriously great deal on renting her apartment and cafe (in Tokyo, no less). Then she gets sent back in time to 1999 before the Project Gaia catastrophe and meets a young man named Tohru and the two fall in love. It turns out that he grows up to be her landlord. The TV series also hints that he has something to do with the Tyke Bomb project that produced her.
 * In the Lupin the Third movie Elusiveness of the Fog, the three guys are sent back in time by a guy from the future. Originally, he just wanted to kill Lupin, but when he was testing his time-machine, he saw a rock vanish before his eyes, proving that it had been erased in the past. He assumed that Lupin somehow managed to steal his time machine and made the rock vanish. Turns out, while he was trying to kill Lupin (in the past), he accidentally blew up the rock, making it vanish (in the present), and in the process causing himself to freak out and go to the past...
 * Oh, and his initial reason for hating Lupin was because in the future, Lupin's identical descendant hooked up with the girl he liked the day he was planning on proposing to her. Disproportionate Retribution anyone?
 * When Geronimo goes through a trial to become a true Chojin, he enters a canyon where he and his sister got lost as children, but were saved by a mysterious stranger. While he's there, he finds another little boy and girl who've gotten lost, whom he saves. After saving them, he realizes that he was the mysterious stranger, sent back in time to save himself and his sister via STL.
 * This almost happened in Seikimatsu Occult Gakuin
 * Doraemon is fond of this. Many time the titular character and Nobita time-travel to fix an event in the past only to find out that they are actually the culprit of what they are trying to fix.
 * In Gall Force, the spacecraft used to  in New Era bears a striking resemblance to the one shown in , which suggests that
 * In the 3rd Fairy Tail OVA, after being sent back in time,
 * Viewtiful Joe once stole his own cheeseburger through this method.
 * Viewtiful Joe once stole his own cheeseburger through this method.

Comic Books

 * Maybe the best example is given by Universal War One: the whole plot is based on not one, not two but three nested stable loops, without any Plot Hole.
 * Brilliantly subverted in the comic strip Calvin and Hobbes. It's 6:30 and Calvin doesn't want to do his homework, so he decides to Time Travel forward to 8:30. Then he can pick up the now-finished homework, bring it back to 6:30, and goof off the rest of the evening. But it doesn't work. There's no homework to pick up at 8:30 because Calvin never actually did the homework -- he went time traveling instead.
 * The best part came, of course, when they BOTH decided to go after 7:30 Calvin, because he was the one who was supposed to be doing it. That didn't work either.
 * Eventually, it indirectly does work. Both the 6:30 and 8:30 versions of Hobbes wrote a story about how stupid Calvin was to attempt this plan in the first place. It got Calvin an "A+" for creativity.
 * In The Invisibles, Gideon is introduced to The Invisible College by an elderly Edith Manning, who recognises him as a time traveller from her youth. After entering the college, he is taught to Time Travel, which results in him going back and meeting her as a young woman...
 * The elves in Elf Quest are only on the planet because their alien ancestors ("the coneheads," later termed "the High Ones") were attracted by the human tales of elven beings. The coneheads shapeshifted into elven beings and turned their spacecraft into a palace, then, as they were landing, were flung back to the caveman days, where all their powers stopped working and they were nearly killed. The few survivors founded some cultures that became the elves that begat the stories that prompted the coneheads to attempt to land in the first place.
 * Later on, the magic-user Rayek attempts to stop the event that flung the High Ones into the past. It's pointed out that those who were born as a result of this event would cease to exist should he succeed, but he doesn't care (except, it seems, for the few he knows personally). He's talked out of it by the three people most dear to him, who choose to suffer the same fate as the planet; as Rayek can't bring himself to erase them, he stands aside and lets the event happen as it already has.
 * His plan, more specifically, was to merge the two magical spaceships (the actual one and the one that took The Slow Path for 10000 years) and prevent the time loop by making the spaceship stable through the power of applied Object Paradox.
 * In the Marvel Universe, Cable was infected by a techno-organic virus by Apocalypse, who, it is revealed later, got the virus in the past from Cable.
 * In the Elseworlds book Superman Red Son, it's revealed that Superman was sent back in time as a baby, because
 * Ironic in that
 * In one story, Superman is shown a vision of the future, and sees a superhero codenamed Sirocco (which means The Desert Wind in Persian). Later, when Superman visits Iran and befriends Sirocco's present self, he accidentally calls him by that name. The man says the name is cool and asks Supes if he can use it for his codename.
 * The original Legion of Super-Heroes seems to be an example of this--they were inspired by Superboy, and they make him a member and have him fight alongside them, arguably shaping him into the hero who inspired them.
 * The final pages of Ultimate Fantastic Four #53 show that, which precipitated his rise; when he lost it,.
 * In Tales From the Bully Pulpit, Teddy Roosevelt gets help from the "Teddy of thirty minutes from now" (a reference to the Bill and Ted example below). At the end of the story, the main characters remember to go back and fulfill the time loop before going off on their adventures.
 * In Amazing Spider-Man Annual #20, Arno Stark, the Iron Man of 2020, has developed a time machine that received military backing by an atomic bomb project that he is also developing. An anti-war terrorist locks up Iron Man's wife and son in the laboratory which contains the bomb, but is killed by Arno soon afterward. To defuse the bomb, Arno uses his time machine to go back to the 1980s to get the younger terrorist's retina patterns. In doing so, though, Iron Man becomes involved in a fight with Spider-Man which results in the child becoming scarred -- giving him the motivation against Iron Man in the first place.
 * It gets worse... Not only did Arno not get the retina scan he needed (the scanner was destroyed in the fight),
 * Alan Moore's Supreme has two stable time loops, one forming the main plot of the initial plot arc, and a second in a single issue as a comic parody of the trope. It's strongly implied that
 * Larry Hama's Nth Man the Ultimate Ninja is entirely encircled by a time loop.
 * 52 has two of them in the Booster Gold plot line. One of them has . The other has Booster   Both were created due to the actions of.
 * himself is also a stable time loop: he reveals that he's
 * Best one ever: The whole reason for Imperiex's existence during Our Worlds At War is that the multiverse is flawed, so he seeks to destroy everything to re-create it. As a force of nature, he can't be destroyed: to wit, when he seems defeated, his energy was merely absorbed by Brainiac, who then starts a plan to assimilate the universe with that power. Superman has a huge problem: If he destroys Brainiac, Imperiex gets free and can "hollow" the multiverse. But if he leaves Brainiac be, the multiverse will be assimilated. What does Superman do? He arranges for a Time portal to be opened and pushes Brainiac/Imperiex (who are the size of a PLANET) into it, taking them to... a milisecond after the Big Bang. Their essences get in the way of nature, forming our flawed multiverse instead of the "perfect" one that should have been, but making sure that neither is a problem from there on out in the present.
 * Flash: Rebirth has used this to retcon
 * One Silver Age Superman story featured Kristen Wells, a researcher from the future who traveled back in time to find out who the mysterious superhero "Superwoman" was. Unable to find her anywhere, she eventually realizes it was she herself, so she puts on the Superwoman costume and uses future technology to do all the superheroic feats that future history books claim Superwoman did.
 * In The New Universe, it is revealed that the Old Man is an older Ken Connell, who was thrown back in time and, thanks to the power of the Star Brand, lived for centuries before accidentally initiating the White Event and giving his younger self the Brand.
 * One Radioactive Man comic from the 1960s features a villain being sent back to the 1860s via a Trans-spatial Stair Climber. When a damaged robot appears out of thin air, he repairs it and programs it to kill Radioactive Man before placing it in a time capsule due to be opened in 100 years time. At the end of the comic, the robot is damaged by Radioactive Man before being hit by Dr. Broom's Time Machine Gun - and sent back to 1863. When Fallout Boy wonders about who built the robot in the first place, Radioactive Man reminds him that "we're dealing with two mad scientists, and that's a pair o' docs left well enough alone."
 * The Uncle Scrooge story, "Of Ducks, Dimes, and Destinies," features Scrooge's nemesis Magica DeSpell travelling back in time to steal Scrooge's legendary number one dime. The man who was supposed to pay Scrooge the dime for a shoeshine decides to go out for a drink after Scrooge passes out shining his ridiculously muddy shoes. Magica intercepts the man and steals the dime, only to realize that since she stole it before it was given to Scrooge, it is no longer the first coin earned by the world's richest man (the last component she needs for a spell to create an amulet that can turn things into gold). Magica winds up giving the dime to an unconscious Scrooge, completing the loop.
 * Rita Wayword was captured and changed into the Multi-Armed and Dangerous Spiral... when Mojo sent Spiral to attack her past self.
 * She Hulk once dealt with a rather complicated Stable Time Loop for her law firm. The case: A billionaire named Charles Czarkowski shot an unarmed man (dubbed "John Doe"), in the back, in broad daylight, in front of a dozen eye-witnesses, and it was caught on film. Czarkowski claimed that before the shooting he received a message from the future warning that John Doe was destined to shoot him, and Czarkowski shot him in self-defense. Fearing for his life when a time-robot attacked the courtroom, Czarkowski traveled through time, used a DNA scrambler to alter his appearance, and tried to send a message back in time to warn his past self. But when he saw his altered face in the mirror he realized that he was John Doe all along. The message he sent to warn himself accidentally implicated his future self in the murder of his past self. Then the Time Variance Authority showed up and forced Czarkowski to go back in time again and get shot to maintain the time loop. On the plus side, the TVA had to drop the attempted murder charge against him.
 * Robo finds himself in one of these in Atomic Robo and the Shadow from Beyond Time, where three future versions of Robo instruct him to learn the hell out of hyperdimensional mathematics so he can return to that point in time-space to defeat the Eldritch Abomination they're fighting. It's not a true Stable Time Loop, of course, because Robo is very insistent that there's no such thing as time travel.
 * When Sonic the Comic did an adaptation of Sonic CD (a game where time travel is one of the main mechanics), it pulled off a loop so neat that, in the last part of the story, they could reprint an unedited page from an earlier issue and have it make perfect sense and not seem like laziness on the part of the writer or artist. (The first time the page appeared, the audience perspective is that of present Sonic; the second time, we're following future Sonic, who's been shrunk.)
 * In H-E-R-O, this is the fate of the HERO dial. At the end of the series, it gets thrown back in time, where it's found by its very first user, who featured in a Whole-Episode Flashback earlier in the series.
 * Thor's grandfather, Bor, was defeated in battle against Frost Giants. He did not expect them to use magic, and therefore wasn't protected when a sorcerer cursed him and turned him into living snow. He told his son, Odin, to find a stronger sorcerer and undo the curse, but Odin stalled for years. When Thor was born, Odin noticed he had Bor's eyes, and was ridden with guilt Bor's spirit came to him and told him he'd be forgiven if he adopts a child who's father he'd kill in his next war. As it happens, Odin's next war was against Frost Giants as well, and the child whose father he killed was Loki. Thus was Loki adopted as an Asgardian.
 * Thor's grandfather, Bor, was defeated in battle against Frost Giants. He did not expect them to use magic, and therefore wasn't protected when a sorcerer cursed him and turned him into living snow. He told his son, Odin, to find a stronger sorcerer and undo the curse, but Odin stalled for years. When Thor was born, Odin noticed he had Bor's eyes, and was ridden with guilt Bor's spirit came to him and told him he'd be forgiven if he adopts a child who's father he'd kill in his next war. As it happens, Odin's next war was against Frost Giants as well, and the child whose father he killed was Loki. Thus was Loki adopted as an Asgardian.

Fan Fiction

 * The Harry Potter Slash Fic Mobius by geneticallydead.
 * Harry Potter and the Methods of Rationality has four of these to date, the most notable one being when
 * His attempt to use Time Loop Logic (see Real Life below) as a manually-performed perfect algorithm was... less than successful. The output:
 * Kyon: Big Damn Hero has these every few chapters, and so many that any unresolved ones are offering As soon as he resolves the last one...
 * Yabba Dabba Joes -- Destro went through almost three dozen agents trying to kill members of the Joe team in their cribs before finally accepting that time travel in the Joe-verse doesn't allow changing the past.
 * Paradox has a stable time loop despite the name.
 * One Harry Potter fanfic (name escapes me) had a four year old Harry being sent back in time to when his parents were newly married. In the end . ...yeah.
 * In the Axis Powers Hetalia fic Chasing an Empty Dream,.
 * In another Harry Potter comedy slashfic (possibly Harry Potter and the Sword of Gryffindor?), Hermione steals a time turner for the purposes of "kinky sex" that will also hurt Death Eaters. This is explained by Hermione at the time saying that she sort-of got it through a time paradox, but not to worry about it. Later, Harry is sent to put it back in the Department of Mysteries at the same time as stealing it in the first place. On the way, he runs into Mad-Eye Moody, who says that the DoM is being guarded after the events of Harry Potter and The Order of The Phoenix and that he should probably not venture in there. Upon exiting in failure, Hermione suggests that he just give her the one that he had to put back. This leads to Harry having a Logic Bomb moment along the lines of "But you gave this to me after traveling through time... and I just gave it to you... where did it come from?!"
 * The Marvel-verse fanfic Dreams of the Waking Man In the far future, Deadpool helps Cable and Hope to return to the present, which causes a chain of events that influences the entire Marvel universe

Film
"McCoy: You know, if we give him the formula, we'll be altering the future.
 * Triangle has a very convoluted one.
 * Bill and Teds Excellent Adventure: Bill and Ted demonstrate remarkable Genre Savvy by using Stable Time Loops to their advantage. For example, in the first film Ted's father has lost his keys; when Bill hits upon the idea of setting things up using time travel, he suggests they could go back, take the keys, and hide them somewhere; they immediately check the location and the keys are there. They're also careful to remind themselves that they need to set things up when they're done with the history report, otherwise it won't happen.
 * Also, they hear their future selves call Rufus "Rufus", which is why they use that name for him later when they become the future selves. He never actually tells them his name.
 * The climax of the second film revolves around this, as both Bill and Ted and Big Bad Denomolos try to use the same plan against each other; the boys disarm Denomolos with a sandbag and trap him in a cage, but he produces a key and a new gun. When the gun turns out to be a "BANG!" Flag Gun (that says "Wyld Stallyns Rule!"), the boys point out that only the winners can play that game, and they set up the key and gun to fool him.
 * In The Final Countdown, the USS Nimitz goes back in time from the early 1980s to just before Pearl Harbor. This not only meant that person was present for the events but sending him to the Nimitz delayed her departure, which could have been what put her in the right place at the right time to be sent back in time.
 * Donnie Darko: However, this is never explicitly stated, resulting in a certain amount of Mind Screw.
 * In Grizzy Mountain, two kids go back in time to 1871. They're the ones who are responsible for keeping Grizzly Mountain from being blown up, and allowing the Natives to keep their land.
 * In The Terminator, the world-ruling SkyNet computer attempts to defeat the human resistance by sending a Terminator android back in time to kill the mother of resistance leader John Connor before he was born; not only does the Terminator fail, it turns out that if SkyNet had not made the attempt, Sarah Connor would not have met John's father and John would not have existed.
 * In addition, the sequel (and a deleted scene from the first film) reveals that the technology used to create SkyNet was developed by researchers studying the remains of the Terminator android. Thus, the SkyNet technology was never invented by anyone, but came into existence within the time loop.
 * In theoretical physics, the above is known as a 'Picasso Paradox': if Picasso somehow went back in time and gave his younger self reproductions of his paintings, are Picasso's paintings then the result of the reproductions, or are the reproductions the result of the original paintings?
 * This gets played with in one of the Hitchhikers Guide novels: A famous poet had very few of his works survive in any sort of readable fashion, since he wrote them using various natural implements on leaves. Some suits go back in time and convince him to write them properly (pen/paper) and wind up re-selling the poems. The issue here is that his poems were largely about how depressed he was when his girlfriend left him, and with the money and licensing deal that doesn't happen so the execs have to go back in time again get the original leaf copies and have him recopy those without him ever knowing why he would want to write them. But this sort of thing happens all the time and its better just not to worry about it.
 * Then in the sequel to that, the Terminatrix reprograms SkyNet tech to awaken it, thus resulting in the Machine Rebellion, which ultimately leads to that same SkyNet sending back the Terminatrix to awaken itself...
 * Also, in the first film Kyle tells Sarah a message John gave him to memorize. In the second film we see that Sarah has given the message to John, so he can give it to Reese. So who wrote the thing?
 * A very, very detailed analysis of the time loops in the Terminator series is available here. That site makes the interesting argument that what we see probably is not the first version of the loop; information such as Kyle's message was initially generated in an earlier cycle, and mutated with iteration until the versions converged, and we're seeing the final 'stable' cycle.
 * The premise of 12 Monkeys is that Time Travel cannot alter history in any way -- whatever you go back and do in the past, you've always gone back and done in the past. Cole remembers that as a kid, he saw, which later happens just as he recalled it. The researcher (and the other time travelers) went back from 2035 to 1996 for one reason only -- to gather information about the original virus (which had greatly mutated by their own time) of The Plague that had decimated humanity in 1996, so that a cure could be developed in 2035. The near-destruction of humanity in 1996 will always happen; the 'happy ending' is.
 * Star Trek IV: The Voyage Home does this with the invention of transparent aluminum.

Scotty: Why? how do you know he didn't invent the thing!"

"Spock: Admiral, weren't those a gift from Dr. McCoy?
 * In the Novelization of IV, Scotty says that he did invent transparent aluminum, and that it was necessary to show him how.
 * The same thing also happens when Kirk sells the glasses he got from McCoy for some needed money. He even lampshades it.

Kirk: And they will be again. That's the beauty of it."


 * According to Miller in Repo Man, all of human history is a Stable Time Loop. Of course, he doesn't seem the most reliable source on these things, although the rather drug-fueled ending makes it seem a bit more likely.
 * In Somewhere in Time, there is a watch that an old lady gives to Richard Collier. Later on, Richard Collier goes into the past and gives the pocket watch to the much younger lady, who keeps it until the present. Also, Richard Collier's signature from the past in the book in the present - indicating that his trip into the past will be successful.
 * In Time Rider, the protagonist from the present unwittingly goes back to the wild west and meets an attractive young woman. After getting to know her (at her insistence), she asks about a necklace, which he claims his grandmother gave him. Through the course of the film, he gradually realizes that no, these aren't a bunch of really intense historical re-enactors, while she comes to understand that he really is from the future.
 * In Split Infinity, A.J. goes back in time (via Mental Time Travel) to 1929. It turns out that she was responsible for saving the house and the barn from the stock market crash.
 * The original Planet of the Apes 5-film series. You can start at any of the films, and follow them around in numerical order to form the time loop (each film follows the previous one, the first film follows the fifth).
 * Given that the fifth film ends with, the loop looks as if it has been broken (if you ignore the Made for TV series).
 * Not necessarily. There's still a good chunk of time between the 5th and the 1st, more than enough for there to be a falling out and civil war between the apes and humans.
 * This can be placed under either Literature or Film, but both Michael Chrichton's Timeline and The Film of the Book include this trope. In the beginning of the story, the archeologists discover a sarcophagus of a one-eared man buried with his wife, seeming, for all intents and purposes, to be a knight. When the characters go back in time, one of them ends up falling in love, getting an ear cut off, and winds up staying in the past, thereby becoming the man in the sarcophagus.
 * The same could be said of the glasses found during the excavation. The glasses weren't left behind in the past, they were left in an alternate universe. (and if they had the "foresight" to leave the glasses in place in the alternate universe so they could find them in the future of the normal universe just because they knew to leave them in place in the alternate universe past...).
 * La Jetee has two loops in it. The first one starts when the protagonist witnesses a murder as a child and the image of a young lady screaming in horror is burned into his memory. This memory is what allows him to travel back in time from the post-apoctalyptic future, and what causes him to try to escape his superiors and start a new life in the past.  The second loop occurs when the man travels from the ruins of post-WWIII Paris into a future where civilization has returned to its peak, gathers supplies, and goes back to his own time so the supplies can be used to rebuild society and allow that utopian future to occur.
 * Another more odd-ball yet stable time loop is a Spanish movie called Timecrimes Which features a man who, bored with his lonely day, starts spying on the neighbor girl. He witnesses a man in a red mask after her, in his attempt to warn her and chase the guy he eventually ends up in some mad scientist's lab where a temporal pool has been created, he is told to hide in it and sent back into the past. In the past he tries to save the girl but ends up missing him by seconds, finds his car missing so he can't follow the man after he seems to vanish down the road, later that night he sees the man assault the girl, chasing her into her house where she eventually leaps to her death. After this and seeing the masked man's eyes he ends up back at the mad scientists lab he pleads for the man to send him back into the past. The scientists agrees and while in the past the main character tries to find the man with the red-mask and ends up stealing his car and wrecking it into a tree. He then 'becomes' the red masked man, repeated all the previous steps and learned that he himself caused his own time loop by tricking his past self twice into the time-chamber.
 * The Time Shifters avoids this trope for the most part, as time is shown to be subject to change. At the end, however,.
 * Back to The Future has one moment that looks like an example: the scene where Marty is in the past and he plays Johnny B. Goode, by Chuck Berry. Chuck's cousin hears it and calls him to hear it on the phone, implying that's where he got the idea for the song. However, given that Marty has clearly not already changed the past when the movie starts, and Chuck could not have heard enough of the song and Marvin had no opportunity to write down or memorise the lyrics, it should be obvious that this was an example of Alternate Timeline.
 * Brazilian film O Homem do Futuro (The Man from the Future) ends up in one of those. Protagonist Zero ends up going back 20 years to the day of his prom, where he prevents his date from humiliating him, which ruins his life. This changes the future... but not for the best, specially as said date hates his guts. So Zero goes back to the prom again, stops his other time travelling self and instructs his date to humiliate him and not contact him for 20 years (which she does once Zero returns). During the prom, Zero also ends up creating the fortune that financed the time travelling process, by instructing a classmate that became a contractor to buy stock from Google and sell it before the 2008 crash.

Literature

 * Diana Wynne Jones is fond of this. There is a simple one in Aunt Maria where the protagonist and her mother go back in time while turned into cats to watch events unfold, only to become responsible for the events in the first place.
 * In Merlin Conspiracy, (this is a doozy): Nick's part of the story begins with him sidestepping into other universes willy-nilly. A man named Romanov shows up to kill him. After he spares Nicks life, Nick later follows him to his personal island/mini-verse, where he is deathly ill. While taking care of Romanov, a Knight Templar and his two wards (Joel and Japeth) show up to finish Romanov off while he's down. They are dispatched, and one of the boys treads on an egg. Nick laughs. Several universe hops later and Nick winds up in Blest, where there is a ten year difference between Romanov's world, and the two boys are now the Big Bad Chessmasters who kicked off the whole plot to begin with, and are the ones who not only sent Romanov to kill Nick, but also gave Nick a special virus to kill Romanov, which was what made him sick earlier. Which Nick himself accidentally gave them the idea to do. He accused them on Romanov's island -while they were still young- of paying Romanov to kill him. Plus several other, minor time-related things, such as answering the phone while romanov was ill, causing wife to leave him. She winds up being Joel and Japeth's sidekick.
 * There was a short sci-fi story where a king, who is is always coming up with crazy and unhelpful schemes to improve his small country discovers that a time traveler is helping his advisers to offset the impact of his schemes. He captures the time traveler and forces him to take them both into the future so he can how things will turn out. They arrive in ten years in the future and that the country is prosperous beyond his wildest dreams, so he asks a passerby "What was the big change that brought about this golden age?". The passerby answers "It all turned around when the crazy king disappeared ten years ago and the advisers started ruling the nation". As the king wonders why he disappeared a decade ago, the time traveler shuts the door to his time machine, leaving the king in the future.
 * In Douglas Adams' Life, the Universe and Everything, the poet Lallafa was known for writing beautiful poetry on habra leaves in the middle of a rainforest... So some time travelers picked him up from the rainforest and put him on the talk show circuit in the future. Of course, he had to write the poems at some point, so they just sent him back to the forest with a book of his poetry and a bunch of habra leaves...
 * Far from the only Stable Time Loop in the Hitchhiker's Guide to the Galaxy series. Arthur, of course, met with Agrajag before one of the many deaths of his previous forms had ever occurred, and so he knows that he's going to be able to escape when Agrajag tries to kill him anyway. Also, the entire arc with the Golgafrinchams.
 * As explained by Ford Prefect, every form of Time Travel in that universe is a Stable Time Loop.
 * Zaphod Beeblebrox is his own ancestor and descendant.
 * That series of books is definitely Timey-Wimey Ball. People are trying to build an ion factory. They don't finish it in time. so they keep pushing the construction start date back farther into the past, until the cathedral that was originally in the spot was never built in the first place. It then states that photographs of the cathedral suddenly became immensely valuable. Huh? Time travel, like everything else in those books, runs on Rule of Funny.
 * What's more, in the first book, it's suggested that the origin of life was caused by the Infinite Improbability Drive -- which was, of course, later built by living creatures.
 * In the story The Red Queen's Race by Isaac Asimov, an attempt to change history by sending modern scientific knowledge back to the ancient Greeks is subverted when the person translating the information finds out about the plan. The translator creates a Stable Time Loop by censoring the translation to include only odd bits of surprisingly advanced knowledge that actually turned up in the ancient world. Also, it's decided that doing this was necessary for history to happen as it already did.
 * A Stable Time Loop also occurs in Isaac Asimov's The End of Eternity, as well as a paradox that is implied to create our timeline by inspiring fission research.
 * Also implied in "The Final Question" ("Can entropy be reversed?") when the Cosmic AC has finally compiled enough data to come up with an answer (despite the end of the Universe) and says
 * In Jack Chalker's Downtiming the Night Side, a modern-day security officer is drawn into a time-loop by an incident instigated by himself,.
 * Not to mention they
 * The entire plot of Artemis Fowl: The Time Paradox. A picture of Artemis chasing himself through the timestream is on the cover. In going back to the past to rescue the lemur, Artemis managed to draw the attention of the younger Opal Koboi. She then followed them to the future, but arrived a few days early, in order to set off the events that would cause them to time-travel in the first place.
 * Plus, Artemis' adventures in the past are implied to inspire his younger self to research the faeries and begin exploiting them in his schemes.
 * Lester Del Rey's 1951 short story "...And It Comes Out Here" features a time machine that's created by a time loop.
 * In The Last Chronicles of Thomas Covenant Linden travels to the past to get the Staff of Law, since it is nowhere to be found in the present, since she picked it up in the past... And because she picked it up in the past it didn't exist during the intervening years, meaning that Lord Foul and his allies grew stronger because its power wasn't opposing them for all that time.
 * In the Thursday Next Novel The Eyre Affair, Thursday meets herself, and receives the news that the Big Bad is alive, and is told to travel to Swindon. As a result of the travel, she ends up caught in an patch of Bad Time, and arrives to deliver the message.
 * Later in the series, it's revealed that the various methods of Time Travel work on the assumption that someone will invent Time Travel, and deliver that technology to their current time. This starts causing trouble when people find that Time Travel won't be invented.
 * Also, Thursday's father gives her his chronometer. He got it years ago from her, after she got it from him.
 * A debate runs throughout the book about who really wrote Shakespeare's plays. At the end of the book, Thursday's dad, a time traveler, reveals that
 * In Something Rotten, Thursday meets her father when he turns up to thwart and investigate an assassination attempt on her. He's there because of a conversation they had "three hours ago", and refuses to answer Thursday's questions because he's already explained all that and can't be bothered to go over it again. It turns out that through a minor confusion (the aforementioned chronometer is broken, so Thursday gives him "hers"), the previous meeting is in fact three hours in the future from Thursday's point of view. Three hours later, Thursday happens to be passing her father's office and decides to go in to find out what he'd been talking about earlier. At the end of the conversation (which is equally as confusing for her father as the earlier chat had been for Thursday) she mentions that she was only there because of their talk during the assassination attempt, and her father agrees that perhaps he should go and investigate...
 * The Robert L. Forward novel Timemaster demonstrates the use of a Stable Time Loop generated by a wormhole (technically, a "closed timelike curve") as an offensive weapon.
 * Harry Harrison dumps The Stainless Steel Rat into Stable Time Loops so often that Jim treats it as a normal occurrence. Usually they're fairly brief, but The Stainless Steel Rat Saves The World is a novel-length stable time loop. Or more accurately, it's one stable time loop after another for the whole book, with one unstable time loop for variety.
 * Another Harry Harrison book, The Technicolor Time Machine, hinges on several Stable Time Loops. The premise is that a movie studio is about to go bankrupt, and so in desperation they try funding a seemingly crackpot physicist who's working on a time machine in exchange for the use of the completed model. It works, of course, so they take a camera crew back in time to film a historical about how the Vikings discovered America - they don't have to pay for sets or actors this way, and they can get the whole film done in a couple of days so they'll be able to show the bank that they have an asset they can monetize when the next loan payment becomes due. When they find the Viking that history says is the discoverer, however, he seems completely uninterested in attempting the journey... until they nudge him with a little bribery and technical assistance. A few other Self-Fulfilling Prophecies occur later on, including a note that nobody wrote and
 * The Robert A. Heinlein short story "All You Zombies" uses the same device. The protagonist tells a bartender a story in which he
 * In The Door Into Summer,
 * James Hogan uses a Stable Time Loop approximately 50,000 years long in the third book in the Giants series.
 * A short story by Anne Lear, The Adventure of the Global Traveller, has Sherlock Holmes' nemesis Moriarty steal the Time Machine (from H.G. Wells' story), only to have it break down (and completely disintegrate) on stage at the Globe during the first performance of Macbeth. Moriarty recites the Third Murderer's lines as he recalls them from reading the play; afterward, Shakespeare is delighted with the new lines and writes them into the script. Like Ashbless's poetry below, no one ever wrote the lines: the first time they were spoken it was from memory...
 * Time Travel in the Dragonriders of Pern books by Anne McCaffrey operates on this principle. Much of the Time Travel is undertaken knowing in advance that it will work ("since I've already done it, I might as well go do it..."). What isn't, is of the form "I think I'm the one who did it, so I'd better go do it..."
 * Behold the Man by Michael Moorcock: Karl Glogauer tracks down the real Jesus, son of Mary, and finds that he's an idiot; so he...
 * The Time Traveler's Wife by Audrey Niffenegger is full of Stable Time Loops. For example, on one of Henry's visits to his wife-to-be Clare in the past, he dictates to her a list of dates in her childhood when they're going to meet. They meet on those dates only because she knows he's going to appear -- there are some other times when he appears, but since those dates aren't on the list, she doesn't know he's there. When they meet as adults in real time, she gives the list back to him so he can memorise it. Where did it come from in the first place? Seemingly nowhere. Henry also taught his younger self a number of skills he knew he would need, such as how to pick locks. His theory is that to prevent Temporal Paradox, he has free will while he's living in normal time but not while he's time traveling.
 * One time loop is Henry and Clare's marriage. From Clare's perspective, she meets Henry when he travels back in time to her childhood, lands in her backyard, and introduces himself as her future husband. From Henry's perspective, he meets Clare when he runs into her in a college library and she tells him that she's known future-him for most of her life and that they're going to get married. So when did they meet for the first time? The answer is "Both": He first met her at the college library, and she first met him in the Meadow. Because of Time Travel, they both met a version of the other who was ignorant of their future relationship/marriage.
 * In H. Beam Piper's short story Flight from Tomorrow, a tyrant in the very far future forces a scientist to create a time machine for him as the ultimate escape route, and he uses it to flee into the past from a rebellion at the beginning of the story. He is not expecting a Stable Time Loop - quite the contrary - but the scientist not only left out some important information but sabotaged the machine, so that he went back not to the time he had researched, but to the mid-twentieth century. The tyrant is hunted down and killed as a plague-carrier. The scientist in his own time explains to the rebels that they cannot pursue the tyrant into the past, or they will meet the same fate; the scientist's audience realizes that a mysterious artifact from the distant past must be where the tyrant's body was covered over with concrete to prevent further contamination.
 * In The Anubis Gates by Tim Powers, the protagonist, Brendan Doyle, becomes the victim of Grand Theft Me in the 1800s and realizes that he is destined to be the poet, William Ashbless, whom he was researching in the present day. Partway through the book, he panics on realizing nobody ever wrote Ashbless's poetry -- he copied it from memory earlier -- but then shrugs it off, deciding that as long as it was there, nobody would be bothered.
 * The Discworld novel The Last Continent is essentially a single, but quite complex, Stable Time Loop, in which the problem Rincewind has to solve is caused by the wizards accidentally going back in time while looking for him. It also includes Ridcully dismissing Ponder Stibbons' worries about the Butterfly of Doom (or Ant Of Doom in Ponder's example) by concluding that history depends on you treading on the ants you've already trodden on.
 * Specifically, Ridcully's argument relies on the old "you can't step on an ant if you don't exist." His logic is that if they're in the past NOW, then they've already been there thousands of years ago, when it was now. Therefore, anything they do, they've already done (because it's the past and the past has already happened), and it's vitally important that they do whatever they do, because if they didn't, they wouldn't have done it and they'd have done the different thing instead.
 * Night Watch subverts a Stable Time Loop: there was a real Sergeant Keel the first time around, but Vimes' and Carcer's arrival from the future gets him killed ahead of schedule. Vimes must assume Keel's role to force stability on the Loop, and while the general outcome is the same, several of the specific events are different.
 * On a smaller scale, minor recurring character Mrs. Cake is a psychic who is known to answer peoples' questions before they ask them; she then insists they ask, to stabilize the time loop, or she'll get a migraine.
 * In Interesting Times, Hex answers a problem before it is asked. The wizard in charge eventually enters the problem to appease causality, but not until hiding in the privy for an hour and a half.
 * In Eric, Rincewind travels back in time to before life existed on the Discworld, and drops a partially-eaten sandwich in a tidepool. The microorganisms in the tidepool become the ancestors of all life on the Discworld, including Rincewind (but not including the sandwich ingredients, because the sandwich didn't originate from Discworld; it was given to Rincewind by the creator of the universe).
 * Played with extensively in Pyramids, particularly in the construction-crew's "doppelgangs" and . The paradoxes entailed are lampshaded when the engineers discuss the option of paying their loop-duplicated workers with loop-duplicated money.
 * In Soul Music, Susan travels to the past and sees her father fight Death at the conclusion of Mort. Death spots her watching and recognizes her as the child of Mort and Ysabell, which convinces the Grim Reaper to stabilize the loop and spare his apprentice so the girl he's just spotted can be born.
 * Also the first paragraph of the book takes place later in the story, despite being chronologically first.
 * In I Shall Wear Midnight,  insists this trope is not in effect, as each iteration of this time-traveller's encounter with young Tiffany will actually result in a different conversation. The fact of their encounter is stable, but the details aren't set in stone.
 * Harry Potter and The Prisoner of Azkaban. Harry is saved from dementors by a Patronus Charm cast mysterious figure who he thinks is his father. After he travels back, he eventually finds himself in the same place and waits for his father to show up... and then realizes HE was the mysterious figure, and saves himself. In fact, he only gains the ability to cast a true Patronus for the first time because he realized that he had already done it. Also, as Harry, Ron, and Hermione first head out to adventure, they hear noises that turn out to be Harry and Hermione as they complete adventure!part I.
 * Stable Time Loop is often used as a justification for being unable to change history in the Potterverse, but it seems to contradict what Hermione tells Harry in Prizoner Of Azkaban about wizards and witches having to be careful to avoid killing their past and future selves. One can explain this in various ways, but the end result is that canon is not entirely clear.
 * Probably it was a mistake made by J. K. Rowling, who did not realise that killing your past self would have caused a paradox. In-universe, it could be explained by Hermione being nervous about what they are doing that she makes that mistake - or else someone made that mistake, but was able to send notice of what he had done.
 * Or, they could have lied to her.
 * In The Green Futures Of Tycho by William Sleator, the protagonist learns to use his time machine from his future self, who only knows how to use the machine because he learned it from himself.
 * Possibly subverted in the Star Trek Deep Space Nine Expanded Universe trilogy Millennium, which involves a convoluted Quasi-Stable Time Loop in which the actions of a future Picard, Vash, and Nog help cause the creation of their alternate future, followed by the retroactive destruction of that same future. During the story both Dax and Miles O'Brien continually insist on maintaining a Stable Time Loop, but by the end it seems their actions can only succeed because of three people who shouldn't exist.
 * In the Warhammer 40000 novel Desert Raiders, a Tallarn regiment is dispatched to an uninhabited planet to investigate a mysterious psychic distress call. After landing on the planet, the regiment encounters a Tyranid splinter group and is forced into a desperate last stand. One of the psykers traveling with the regiment dispatches a warning signal in their final moments -- the same signal the regiment had been sent to investigate in the first place. The implication is that, in traveling through the Warp, they had gone back in time before reaching their destination; indeed, the Warp in the 40K 'verse is known to do some strange things to the flow of time...
 * In Animorphs, In the Time of Dinosaurs, the Animorphs go back in time to the Cretaceous, fight the antlike alien Nesk for a nuke to explode (so that they can undo the time travel) and the Nesk divert a comet to the only home of the Mercora (the friendly aliens). The Mercora wanted the nuke so that they can explode and stop the comet from hitting, but Tobias and Ax rig the nuke not to explode, as the comet was the one that ended the dinosaurs (opening the way for humans to evolve). The force of the comet ends up sending the Animorphs back home.
 * Dragonlance Legends reveals that humans, elves, and ogres can time-travel only to observe. This is how it's supposed to work. Throw in the unnatural races, which were not created at the beginning of time, like dwarves, gnomes, and kender, and you have problems. So,
 * Played with in Kurt Vonnegut's Slaughterhouse-Five where the character lives in a personal unending non-chronological time loop where he lives out every moment of his life repeatedly, with all of his own memories, after becoming Unstuck in Time. In the novel he is suggested to have lived out all these moments more than once and always does the same things every time making it a stable time loop of sorts...
 * The Man Who Folded Himself: A young man inherits a belt from his uncle that allows him to travel to any time in the past or future. In doing so, he meets multiple alternate versions of himself, eventually reaching the point of Ultimate Narcissm, in two extremes. He winds up in sexual relationships with his multiple selves. The second extreme is where things get twisted and yet allows the Stable Time Loop. He gets bored with all of his alternate selves, and humanity as a whole, and decides to try to go back far enough in time to meet an alternate self so far from his own reality they are unrecognizable except by the belt they wear. The one he finds, exactly 1000 years before his date of birth, is a female version of himself. This then begins yet another sexual relationship, resulting in a child. Then comes confusion as the story slips between the two perspectives of the "parents," each wanted a child of the same gender as themselves. So they go into the future, get technology to make sure their child is the "correct" gender, and somehow, even though it is implied that only one child is born, both get their wish and bring their child to the future. They then take the role of Aunt/Uncle to that child, and the cycle begins anew. Gives a whole new meaning to the song, "I'm My Own Grandpa."......and father, and great-grandfather......... The book contains only one character, everybody he meets is a past, future, or alternate-reality version of himself.
 * This is specifically not an example of this. The book lays out the rules for how its time travel works, and they necessarily exclude stable time loops. In fact, the Dan at the end of the book is explicitly not the same as the Dan at the end of the book, for reasons that should be obvious if you've read the end of the book.
 * One book continuity of Red Dwarf or the other puts Lister as the creator of the universe, having gone back to that point in time to see what happened.
 * The William Tenn short story "The Discovery of Morniel Mathaway" is built around a stable time loop that involves an art historian meeting the object of his research.
 * The short story entitled The Sky Looked Strange Today involves a man driving on the freeway when he is distracted by a peculiar aurora on the horizon. When he looks back at the road, he crashes into a taxi cab that has started a pile-up, but time slows down for everything but the man. He gets out of his car into a motionless world when suddenly, his "guardian angel" appears and tells him that his next door neighbor caused the crash. He takes the man back in time, one hour earlier, and leaves him to figure out how to stop the pile up. In an impulse effort, the man slashes his neighbor's tires and, feeling he has succeeded, takes a cab to work before his past self sees him. As he rides in the cab, he notices the aurora again. Unfortunately, so does the driver. The man forgot that his neighbor works for the cab service. So, the neighbor rear-ends a car, causes the pile up, and just before the man is killed by his past self (still distracted), he says his odd last words: "The sky looked strange today..."
 * To Say Nothing of the Dog is built entirely around this trope. The main characters spend virtually the entire length of the novel time traveling back and forth to the Victorian era, trying to correct the actions of one of them that threatens to change the entire course of history.
 * Used quite effectively in Simon Green's Deathstalker series. Simon Deathstalker and his companions
 * In Andrey Livadny's Ark,
 * Time travel in Poul Anderson's novel There Will Be Time seems to require these.
 * In "Explain the Internet to a 19th Century Street Urchin", from the book ''Everything Explained Through Flowcharts", these are some of the more favorable outcomes. The non-temporal outcomes usually result in your death.
 * The Doctor Who short story collection Short Trips: Time Signature follows a single piece of Vortex-threatening music through the Doctor's life. Since the book is in extreme Anachronic Order, following neither the music nor the Doctor linearly, it takes a bit of working out, but essentially the music was sent to the planet where the Doctor first heard it by someone who'd heard it from the Doctor.
 * The events of the novel The Stone Rose begin because Mickey sees a statue of Rose in the British Museum. By the end of the story . In the same book, a vial of mysterious liquid turns out to have been created by the Doctor, by running the dregs of the vial through the TARDIS's Matter Replicator, and taking the result back in time.
 * The Fourth Doctor short story "Breadcrumbs" has the Doctor going to a lot of trouble to collect various three-dimensional data fragments and run them through a reversed Matter Disperser in order to find out what they are. The last fragment is very close to a wormhole, and he just has time to register that the "message" is another Fourth Doctor, before he gets sucked into the Vortex, and ends up on a deserted island on an unknown planet. His only hope is to rewire the Matter Disperser correctly, and transmit himself as a series of three-dimensional data fragments...
 * There and Back Again by Pat Murphy has a mysterious note in the protagonist's handwriting that appears at the beginning of the book, and a mysterious message asking for help that gets a number of secondary characters to arrive at the climax of the book in time. Both turn out to have been sent by the protagonist himself at the very end of the book, after he goes back in time.
 * A common theme in the Xeelee Sequence books by Stephen Baxter. The Xeelee, who first evolved who-knows-when-and-where, reach back in time to refound their civilization at the very beginning of the universe. This gives them a multi-billion-year technological jump, which they'll need to fight a war which would have destroyed them long before they could reach back in time.
 * There is a short story about a man who, while his wife is away, encounters a girl in her 20s who looks a somewhat familiar wearing a strange-looking dress that comes out of the woods. She talks to him a little and then goes back to the woods. She proceeds to return several times and, eventually, tells him that she is from the future. Time travel is a possibility where she's from, but the government has banned it for fear of changing the past. Her father secretly built his own time machine before his death, as he belied that time is immutable and everything has already happened. In the meantime, the man's wife starts to act a little strange towards him, as if she suspects he is spending time with another woman. The girl is missing for several days, and then comes back saying that this is her last visit, as the time machine is about to break down due to lack of maintenance. There may be enough left in it for one more trip. As she disappears into the woods, he follows her but sees only a bright flash of light. He returns to the house and.
 * Warrior Cats also features one. In Starlight, the cats find a perfect (and uninhabited by other cats) spot to live. If there had been other cats, they wouldn't have been able to stay there. Later, in Long Shadows,  Also, in Outcast, Jayfeather met the Tribe Of Rushing Water, and learned their customs. Then, in Sign Of The Moon,   However, both times Jayfeather is trying to create said time loop.
 * The entire plot of When You Reach Me is Miranda slowly discovering that she is in the middle of one of these.
 * Sergey Lukyanenko and Yuliy Burkin's novel Today, Mom! has two brothers being taught Ancient Egyptian by their archaeologist mom. They end up discovering a time machine inside an ancient artifact and traveling to the future and then the past. After saving a young girl from being married to a dying pharaoh (she would be buried alive with him), they take her to the 20th century and leave her there to start a new life. When they get back to their own time (1993), they are attacked by the mummy of said pharaoh who has come back to life. Suddenly,.
 * A millennia-long time loop is central to the plot of Aleksandr Zarevin's Lonely Gods of the Universe, although it's not revealed until the second half of the book. Of course, the characters realize that the time loop is far from stable and will inevitably collapse after 5 or 6 cycles (what that means is anybody's guess), destroying everyone and everything in it. They spend the rest of the novel trying to break out of the time loop, namely by, while making sure that their present selves stay alive. Let's just say the temporal mechanics get very confusing by the end.
 * A smaller time loop occurs in the middle of the novel. The main character is asleep in his apartment, when he hears a loud thud in the next room. He finds a strange object that appears to have been neatly sliced diagonally. Not sure what to make of it, he throws it in the back of his closet and forgets about it. A year later, him and his friend are experimenting with a strange machine they built, which appears to be a mix of a teleporter/portal. One of the tests is a long object specifically made for this. In the middle of the test, power cuts out, resulting in a Portal Cut. However, the part of the object that went through is nowhere to be seen. The main character quickly runs out and brings back the other part from his closet, explaining what must have happened. Eventually, they get additional funding and turn it into a Time Machine.
 * Comes up in Dinoverse. Bones from a large dinosaur closely related to Tyrannosaurus Rex were found at a site called the Standing Stones, a series of, well, standing stones. Bertram puts a shard of one of those bones in his science fair project, which accidentally turns out to be a time machine that sends his mind, and those of some people around him, into the past and into the bodies of dinosaurs and a large pterosaur. They get a message from the distant future, sixty years after the time machine came on, telling them that their bodies had been in comas for sixty years but someone had found a way to fix things. If they could just get to the site of the Standing Stones, they could go back. On the way there is discussion as to whether they'd already failed, and when they got to the place there were no stones, plus they got attacked by a large Tyrannosaur and barely managed to kill it. Turns out it was the same dinosaur, and they had to set up the stones themselves before they could go back.
 * Count and Countess makes use of this frequently. The two main characters, Vlad Dracula and Elizabeth Bathory, have been writing letters to each other across time since they were young children, and often what one character writes to the other will have a large impact on the recipient's timeline, depending on how he/she acts on it.
 * In Barrington J Bayley's novel "The Fall of Chronopolis", a gay man called Narcis travels back five years to seduce his younger self away from the latter's boyfriend. Five years later, they realise someone will soon arrive to destroy their relationship. The book doesn't explain how the traveller didn't remember this had already happened.

Live Action TV
"Present Rory: Do I have to remember all of that?
 * One of Jim's Office pranks involves sending Dwight faxed warnings from "Future Dwight".
 * In one episode of The Red Green Show, one of Ranger Gord's educational shorts had him teaming up with his future self and going back in time to prevent a forest fire. After the two meet and team up with Past Gord, Future Gord explains his information shows the fire will be caused by lightning, which strike Red and Harold. The three Gords violently put out the fire and after looking like the usual "Everybody Laughs" Ending, the three Gords decide to go to the future and celebrate. However, sparks from the time machine taking off end up causing the fire in the first place.
 * The Adventures of Brisco County Jr has the titular character go back in time to meet himself and take a necessary McGuffin out of his own hands. Which is exactly what happened a few episodes ago.
 * Babylon 5 has two of these, related to the same incident. The two-part episode "War Without End" in the third season has the protagonists cause the mysterious time incident on Babylon 4 that happened in the first season episode "Babylon Squared"... at the conclusion of which, an important character travels back even farther in time to become the cause of one of the show's central prophecies.
 * In the first season of the new series of Doctor Who, The Doctor and Rose are followed everywhere by the words "Bad Wolf" - in the final episode, Rose saves The Doctor's life and uses the time-bending power of the TARDIS to deposit the words in the past, in order to inspire her to go forward into the future and save The Doctor's life, which ends in her putting the words into the past, etc., etc. This also crops up a few times in the second and third seasons (since the words were placed all over time and space, there's no reason for them to stop showing up just because they're not needed anymore), and more times than you can shake a TARDIS key at in the Ten/Rose Expanded Universe novel The Stone Rose. The phrase also turns at the cliffhanger of the fourth season episode "Turn Left" (with all written words, from the Doctor's point of view being replaced with "Bad Wolf" -- even the TARDIS' signage), in which it
 * The episode "Blink" also repeatedly uses it. At one point, the Doctor pre-records his half of a conversation with another character; when the other character has the conversation, it's written down, and the Doctor works off it to record his half. Also, his half is recorded as an easter egg on 17 specific DVDs; when the Doctor tells a video executive which discs to put the recording on, he's working from a list someone in the future made of DVDs that have the video on them.
 * Also used "for cheap tricks" (his words) in "Smith and Jones"; when Martha first meets the Doctor, he stops in front of her on the street, takes off his tie, and walks off. When they meet at the hospital again, the Doctor can't ever recall meeting her. At the end of the episode, he goes back in time and takes his tie off in front of Martha in order to prove that the TARDIS is a time machine.
 * Perhaps the most egregious is the possibly non-canonical special "Time Crash", where the Fifth Doctor is brought forward in time and meets the Tenth. A problem develops which the Tenth Doctor instantly solves, working from his memory of when he was the Fifth Doctor in this very situation, watching his future self solve it.
 * This pretty much conflicts with previous multi-Doctor episodes of the original series, where none of his incarnations show any knowledge of the events. Of course, the Time Lords were involved in some way for all of them and may have erased his past incarnations' memories.
 * In the novel Cold Fusion, the Fifth Doctor helpfully lists the reasons future incarnations don't remember the events of multi-Doctor stories from the perspective of their past incarnations, noting that none of them apply to the current teamup with the Seventh Doctor.
 * In the Third Doctor serial "Day of the Daleks", humans from the future attempt to blow up UNIT headquarters to prevent someone from bombing a ministerial-level conference to be held there, starting World War III and allowing the Daleks to invade. Predictably, their bomb is the bomb they are trying to prevent.
 * The Fifth Doctor story "Earthshock" also is an example . So, really a win-win situation.
 * There's also "City of Death", in which an alien whose mind was split several ways across time after his space-ship landed on Earth and exploded. His past selves hid various treasures to be found by his future selves (including multiple copies of The Mona Lisa!), which were to be sold off and used to get the materials to create a time machine so he could go back and prevent the explosion - something The Doctor might have helped with had he not discovered that the same explosion was the "lightning bolt" that stirred up the primordial soup to begin creating life on Earth...
 * Is abused in The Big Bang, in which
 * This episode also features possibly the most pointless stable time loop ever conceived. Young Amelia is thirsty, so the Doctor jumps back in time several hours and steals a drink. He then returns to the present and gives the drink to her. The reason she's thirsty in the first place is that a few hours ago someone stole her drink.
 * Given that Steven Moffat frequently writes in lines that poke fun at Dr Who tropes (Curse of Fatal Death is a long string of these!) this drink-loop is probably employed as an in-joke at how much the trope is being abused in this episode. In fairness though, they do acknowledge it on screen in this episode (and again in The Impossible Astronaut) that they're only able to do all this time-looping because the universe is collapsing.
 * "The Curse of Fenric" reveals that Ace only exists as the result of a stable time loop: she befriends her grandmother as a young woman, and when disaster strikes sends her to a specific address in London with Ace's infant mother.
 * "The Shakespeare Code" is a minor example - the Doctor quotes lines from Shakespeare's works to the man himself. Some of them he recognises, but some of them he hasn't got around to writing yet.
 * This is fairly common in the Historical Domain Character episodes. Donna gives Agatha Christie the ideas for Miss Marple and Murder on the Orient Express; Amy inspires Vincent van Gogh to paint his famous painting of sunflowers.
 * In "Time," the second part of the 2011 Red Nose Day comedy special, we get three of these in as many minutes, two of which play this trope straight (Amy doesn't understand what her future self said, but still says it herself, even though the Doctor doesn't even explain it to her, and the Doctor waits for his future self to tell him which lever to use despite having no idea despite the time loop being a few seconds long) and the third of which justifies it:
 * In "Time," the second part of the 2011 Red Nose Day comedy special, we get three of these in as many minutes, two of which play this trope straight (Amy doesn't understand what her future self said, but still says it herself, even though the Doctor doesn't even explain it to her, and the Doctor waits for his future self to tell him which lever to use despite having no idea despite the time loop being a few seconds long) and the third of which justifies it:

Future Rory: It just sort of happens.

Present Amy, flirtatiously: Hi.

Future Amy, flirtatiously: Hi."

"FARADAY: Time--it's like a street, all right? We can move forward on that street, we can move in reverse, but we cannot ever create a new street. If we try to do anything different, we will fail every time. Whatever happened, happened."
 * As of A Good Man Goes To War, the Doctor's name turns out to be one of these. The meaning of the word was apparently already established when he chose it, but due to centuries of crosstime adventuring, it turns out 'doctor' means healer because of him. However, in some places, it means 'mighty warrior' because of him.
 * In "Forest of the Dead" the Doctor manages to save her imprinted memory, because he figured his future-self wouldn't leave her to die, and his future-self, knowing that he didn't, thus created a way to save her...
 * In Let's Kill Hitler, Amy and Rory make a crop circle as a dramatic gesture to leave a message in time to get the Doctor's attention. They were most likely inspired by River Song's various messages to the Doctor previously in the series. However,
 * Heck, River's whole life is a giant time-loop! She only starting using her signature catch-phrase of "Spoilers!" after the Doctor used it on her the first time.
 * In the Time Travel episode of Ghostwriter, the kids in 1928 solve their case by sending Ghostwriter to 1993 to find out how the case was solved, then bring the info back and use it to solve the case. As the kids in 1993 are reading old 1928 newspapers about the case, the pages start to turn blank -- if they don't send the info back, the case will never be solved and thus the newspaper will never have it.
 * Terminator: The Sarah Connor Chronicles -
 * On the other hand, this is explicitly part of an aversion -- Derek is from a future where Fischer didn't do these things, while his girlfriend Jesse is from the future Fischer contributes to (or at least a future where... oh, no, I've gone cross-eyed).
 * Heroes: Anything to do with Hiro's adventures with Kensei.
 * Near-miss at the end of the second season when.
 * Referenced several times in Star Trek: Deep Space Nine episode "Trials and Tribble-ations". The Temporal Investigations agents specifically loathe Stable Time Loops. Also, Bashir is hit upon by a woman who has the same name as his great-grandmother. After commenting on the fact that nobody knew his great-grandfather, he attempts to argue to O'Brien that he has to go sleep with her in order to ensure his own existence. O'Brien dismisses the notion, causing Bashir to declare that he can't wait to see the look on O'Brien's face when he finds out Bashir never existed.
 * Also happens in Past Tense where Sisko, Bashir and Dax are sent back into Earth's past and Sisko has to stand in for a civil rights leader (who died for the cause) in order to allow the Federation to exist. It is later noted how similar Sisko looks to the historical figure.
 * The Prophets form a part of one. Sisko meets them in 2369, informing them that they are the gods of the Bajorans. That they sent the Bajorans "Orbs". Thing is, the Prophets live in a wormhole, and exist outside of time. From their wormhole, they can simultaneously access any era of history (Shown when they bring an ancient Bajoran to the present, then take him back to his time). So the Prophets, upon being told that this is what they do... do it. They send the orbs back in time, and begin acting as gods to the ancient Bajorans, causing the culture that Sisko gets to know... and then tells them about on his first meeting.
 * Sisko's own existence. Sisko is the Emissary of the Prophet, and discovered the wormhole. This caused the prophets to . The only reason the Prophets did this, is because they met Sisko in the future (and being outside linear time, realized the role they played in his life, and thus took it upon themselves to make it happen).
 * And referenced almost explicitly in the Star Trek: The Next Generation two-parter Time's Arrow, which deals with a similar subject. It's put in as something of a Shout-Out to sci-fi fans: Samuel Clemens (aka Mark Twain) receives his own watch from the Enterprise who have time-travelled back to his period in history after recovering the watch from a cave in the future (and no, it was not made from a BOX OF SCRAPS!). The end of the two-parter concludes with Clemens in the same cave in that time period, looking at the same watch ... and, with a chuckle of amusement, putting the watch down again so the Enterprise crew will find it in the future, thereby sentencing the watch to an eternity inside the Stable Time Loop, as the watch was put there by Clemens to trigger off the loop to begin with.
 * In the premiere episode of Primeval, Nick Cutter discovers a human camp (and human bones) in the Permian, as well as a camera with a picture proving his vanished wife had been there. In the first season finale, having been reunited with his wife, they travel back to the Permian where Helen convinces him to take her picture...which he suddenly realizes is the picture he'd discovered previously, and that the camp they just set up is the one he'd discovered originally. An actual change does happen to the past, however, which confuses things.
 * In the Stargate SG-1 episode '1969,' the team travels back to the title year and has to figure out how to get home, meeting a young General (then Lieutenant) Hammond, two hippies, and a young Catherine Langford. General Hammond sends a note back with them that Captain Carter is not allowed to read until after they go through the gate. The note contains cryptic instructions as to how to get home, as well as instructions from General Hammond to his younger self to help the visitors (that from his POV writing the note he has already helped). It is later revealed that General Hammond has been waiting for years for the sign that it is time to send the note (evidenced by a large cut on Captain Carter's hand).
 * Still on episode '1969', when the SG-1 team manage to travel back to the future, they accidentaly ended up jumping several decades in the future, far from their own time, arriving on a deserted SGC. There, they meet an old Cassandra (the human girl they rescued on a planet attacked by the Goa'uld on season 2), who was expecting them in order to guide SG-1's return to their time, implying that sometime between their return and her meeting with them in the future, she was told to meet them there so they could return to their time.
 * Some fan theories have it that this episode might be the entire reason that SG-1 exists. Hammond knew that the team had to be these specific people, because that's who he saw when they went back in time, so that's who he put on the team. Confused yet?
 * It might even be the reason that the whole Stargate Project exists, by getting Catherine Langford and the government interested in restarting her father's investigation of the strange artifact.
 * Star Trek: Voyager. In "Time and Again" Voyager witnesses the destruction of a civlisation. When Janeway and Paris are accidentally sent back in time a few days before the incident, it turns out that the crew's attempt to rescue them is what triggers the disaster. Fortunately Janeway stops the attempt and the timeline returns to normal.
 * Features prominently in the three-part episode "Future's End". Captain Braxton, from the 29th century, goes back to the 24th century in a single-passenger timeship to destroy Voyager to prevent a 29th century disaster. Voyager fights back, causing the timeship's systems to malfunction and transport both ships to Earth in the late 20th century. The timeship crashes on the surface somewhere around 1967, and Voyager arrives safely thirty years later. Janeway sends down an away team to track down some temporal readings that might indicate a way back to their time when they encounter the now-aged Braxton, who admits that a wealthy 20th century businessman named Henry Starling found the remains of the timeship before he could get to it. Starling then proceeded to reverse engineer the timeship's technology, and used it to kick off the Information Age as we know it with crucial inventions such as the silicon transistor and the integrated circuit. This technology would of course develop over the centuries into computers such as Voyager's in the 24th century, and later the timeship's in the 29th century, which would then get thrown back to the 20th century and crash land...
 * The Red Dwarf episode "Ouroboros" reveals that.
 * In the fifth season of Lost, John Locke may have just created one of his own: Considering his current relationship with the Others, he may have pretty much written his own destiny.
 * An even bigger one occurs in "He's Our You" and "Whatever Happened, Happened":
 * According to Daniel Faraday, this is how time travel in the Lost-verse works, except for Desmond for some damn reason.


 * In yet another loop in the fifth season, in "The Variable",
 * Also in the fifth season, Where did the compass come from? Who manufactured it? Where did it go? Also shouldn't it age into dust? Perhaps it did age into dust, and Richard then created a new one which he gave to Locke and which became the same compass that had aged into dust.
 * Let's just say that Lost has confusing time travel. However, the clearest, unambiguous example of a Stable Time Loop in the show is "The Constant", in which Daniel's journal guides him to tell Desmond certain things to his past self, which his past self then records in the journal before losing his memory. Most notably, the frequency needed to make his time machine work came out of nowhere, since it was passed back and forth between Faraday and Desmond infinitely. Unless, that is, past Faraday already knew the frequency before Desmond showed up, which has always been this troper's impression.
 * The plane crash itself.
 * Stephen Colbert (circa 2009-2509 or so), the main character in The Colbert Report, failed to stop Stephen Colbert (circa 2005-2009) from electrocuting himself, then took his place as host in order to be hosting the show in 2500 to come back in time so he would exist in his present to come back in time...etc.
 * In Kamen Rider Kabuto,
 * Lampshaded in the movie God Speed Love where
 * In the Supernatural episode "In the Beginning," Dean's actions help to set many elements of the series in motion, from encouraging his father to purchase the Impala that Dean later drives, to accidentally focusing the attentions of the Yellow-Eyed Demon on his mother, Mary. The creator of the show noted that the Stable Time Loop concept confused Jensen Ackles a bit. He was told to just go with it.
 * It was stated that what had happened was fate, and that Dean wouldn't have been able to change the outcome. He had been sent back just to witness the events.
 * Which is weird, because an angel later goes back in time to try to change it all. fails, of course, but it has nothing to do with fate.
 * Fraggle Rock: Mokey, researching an ancient leader named Blundig who caused some boulders to be moved, accidentally goes back in time, pretends to be Blundig, and causes the boulders to be moved. In the process, she also makes Fraggle culture closer to what it is in the present.
 * The Book of Pooh has a story that's somewhat close to this trope. The story "Once Upon a Happy Ending" opens with Tigger hanging upside down in a tree with honey jars stuck to his paws. He wonders what's going on and the Narrator explains that he accidentally opened the book to the end of the story. He suggests they go back to the beginning so they can find out what happened and Tigger agrees. It turns out that in the story, Tigger is trying to help Piglet to retrieve an acorn that he lost. Along the way, he gets a couple of honey jars stuck on his paws. Eventually, he learns that retrieving Piglet's acorn would require him to climb a tree, but at this point, he says "no way" because he's already seen what happened. He backs away from the tree, but trips and ends up getting catapulted into the tree.
 * Lesser know TV series Crime Traveller had this where 2 police officers travelled back in time to either stop, or work out, who committed a crime. Often when this happened they had already lived the experience and then travelled back in time to relive it. In the original version of time certain things happened that were strange/funny/helpful etc and it was only when they travelled back in time that they realised it was their future selves that caused these incidents to happen.
 * The Dawn French comedy Anthology Series Murder Most Horrid has an episode in which French plays an inventor working on a time machine. Her simple-minded husband's behaviour becomes so erratic that she bludgeons him to death with a wrench. After serving time for his manslaughter she returns home, completes the machine and travels back to try and stop herself, only to discover that the presence of herself from the future was what caused her husband to behave so annoyingly in the first place. She was even accidentally responsible for the wrench being in just the right place for her past self to pick it up...
 * In Children of the Stones the village of Milbury seems to be caught in a loop where similar characters go through the same set of events again and again. At the end of the series, as Professor Brake and Matthew leave the village, Joshua Litton arrives. Litton is identical to Rafael Hendrick, who had been brainwashing the villagers. The implication is that the story is about to start again.
 * The "Boom Boom Machine" in Fringe originated from a Stable Time Loop.

Music

 * In live performances, the Flight of the Conchords song 'Bowie' is usually preceded by a description of Bret and Jermaine travelling back in time and meeting David Bowie, to whom Bret plays his Bowie's own songs, and even leaves an "easy to play Bowie song book".
 * The Black Sabbath song "Iron Man" is about a person who travels through time "for the future of mankind" only to find that the world is destroyed in an apocalyptic event. Deciding to return to his present to warn the people of the coming disaster, he gets "trapped in a magnetic field" which turns his skin into metal. Thus, when he warns the people of the present, they are frightened by his appearance and too afraid to listen to him. Then, out of frustration that no one heeds his warnings about the forthcoming apocalypse, he causes the apocalypse.
 * "One For the Vine", on the Genesis album Wind and Wuthering, tells the story of a soldier deserting from an army led by a messianic leader. The deserter finds himself on an icy waste populated by primitive people, who see him as a messenger of God. He reluctantly takes the role simply in order to help himself get home, but ends up becoming the very messiah from whom he fled. As he leads his army into battle, he sees one soldier run away from the host, and vanish...
 * Show Of Hands song The Bet is about a man who finds ten grand next to a car crash, takes it, bets on horses with it, wins ten grand and... yeah, you see where I'm going with this.

Radio

 * The Doctor Who audio drama "Flip-Flop" takes this to a rather confusing extreme: Two time loops that feed each other. It's presented on two discs, a "White disc" and a "Black disc", and they can be listened to in either order (or indeed in a continuous loop), as each one follows a different timeline.

Tabletop RPG

 * Continuum is an RPG where the characters' entire goal is to make sure stable time loops work out.
 * Planescape's Faction War features a double time loop. Considering that the person stuck in it tried to overthrow the Lady of Pain, he had it easy.
 * Rulified by the german RPG The Dark Eye in which time travel follows a simple law: you cannot change the past, as it had already happened and you'll just end up doing what you did to create the present you're currently living in. If by some chance the hero does discover some hopelessly contradicting action, be prepared for time to heal itself. Oh, and the universe has wardens against such misuse, too.
 * Get ready for a Mind Screw - in The Chronicles of Fate tabletop RPG, the entire multiverse is one gigantic Stable Time Loop which leads to it also being an Eternal Recurrence scenario.
 * Bizarre version from Warhammer 40000. An Imperial warship picks up a distress call from an Imperial vessel under heavy attack, and goes to respond. When it arrives, it finds no Imperial ship, but the warship itself comes under heavy attack... and sends out a distress call. Thanks to the ability of the Warp to mess with time, the ship went to its destruction answering its own distress call.
 * Another example is of the ork warlord Grizgutz and his army who, after setting off into the warp, arrives shortly before they left off and decides to hunt down and kill his previous self so he can own a spare of his favourite gun. The confusion results in the war-band being stopped in it's tracks.
 * Multiverser features a whole complex system of resolving time loops and paradoxes. Details here.

Video Games

 * Achron has time travel as a major gameplay mechanic so you can set these up yourself. The most common example is to create a base and have it produce an army, then have you opponent attack your base before it builds the army. You can then defend your base by sending back the units that it built in the future. In the final timeline your base survived because it was defended by units from the future, and your units exist because the base survived to produce them.
 * You can even get an even more immediate time loop by sending a mech back in time using a chronoporter. Then, you undo the original build order for the chronoporter and before time catches up, you let the mech build a chronoporter at about the same place. Because the chronoport (the action of sending a unit back in time) is bound to the unit and independent of the chronoporter, the mech will then travel back in time with the chronoporter it just built to build the chronoporter to be sent back in time.
 * Amusingly, a Grekim unit can also literally become its own grandfather.
 * In Sonic the Hedgehog 2006 Princess Elise has a Chaos Emerald as a lucky charm. She loses it and it's found by Silver. Silver goes back in time and gives it to her. The problem? It doesn't exist before Elise gets it, or after Silver goes back in time, and it's never created or destroyed. Also, it means the Earth should have been destroyed by the other Final Bosses.
 * Of course, the events of the entire game were erased from existence in the end, so yeah.
 * Not anymore apparently.
 * And this would have stopped them from being dangerous - Super Sonic wasn't used until after 1996 anyway, so it wouldn't matter, and after it was used, the Final Bosses came from Eggman's emerald collecting.
 * Actually, the world would still have been screwed.
 * In The Legend of Zelda: Ocarina of Time, Link meets a man in the future who is angry that someone in the past used the Song of Storms to wreck his windmill. This teaches Link the Song of Storms, and he goes back in time to use it and wreck said windmill.
 * Meanwhile, Oracle of Ages has quite a few of them, such as defeating the Great Moblin in the present and receiving a Bomb Flower as a reward, then giving said Bomb Flower to the Gorons in the past, who use it to destroy the rocks that collapsed on the Goron Elder while also promising to use its seeds to grow the patch of bomb flowers that the Great Moblin had taken control of in the present.
 * Subverted by the ending of Ocarina of Time. The Time Loop that would have resulted here was so incredibly unstable that the timeline split instead. Now we have 2 universes, one leading into The Wind Waker and the other one leading into Twilight Princess. Yeah, it's even more Mind Screw than the actual Stable Timeloops.
 * Shortly after the release of Skyward Sword, the series' official chronology was released, revealing a third timeline: If Link had died during the fight with Ganon, then the events would have continued into A Link to The Past.
 * In Escape from Monkey Island, there is a puzzle in which you must navigate Guybrush Threepwood through a swamp with time-bending properties. About half way through, Guybrush meets his future self on the other side of a fence. The two of you have a conversation which ends in your future self giving you a few (apparently useful) items and going on his way.
 * A fun part is occasionally, you may be given a gun by your future self. You can use the gun to shoot your future self and carry on as normal..
 * In Ever 17, the main character
 * Fate/stay night. The swords that carries.  can only create a weapon he's seen  However, in the case of his two main swords,  learned to create them from seeing his future self wielding them.
 * Even though the entire Prince of Persia series is based on time travel, the example that stands out most is when the Prince continuously encounters a strange creature through his travels in Prince of Persia: The Warrior Within.
 * The main plot uses this as well. The Prince goes back in time to kill the Empress before she can create the Sands of Time, not realizing that
 * Legacy of Kain: Soul Reaver 2 seems to have one. Once Raziel finds the Reaver broken in half and  throws it away. The most logical thing for Morbius was to   There are actually more of these, but this loop is special,.
 * The first Fallout game has the Player Character trying to find water for their fallout shelter after its water chip is broken. It ends with the PC staying in the post-apocalyptic Earth and heading off to start a new life. The sequel has a random encounter in which the player, now controlling a descendant of the character in the first game, travels back in time to just before the first game and ends up in the shelter. The only way to return to your own time is to break the shelter's water chip...
 * A Stable Time Loop is essential to the plot of Final Fantasy VIII. Because the main party kills in a partially time-compressed realm,  This is what makes, and causes the main conflict in the present that leads to the need to destroy Ultimecia. Additionally, , thus inspiring the creation of the mercenary organization he grew up in and setting up his own role in the events of the game. The Stable Time Loop is further illustrated by the futile efforts at one of the cast members to Set Right What Once Went Wrong; she ultimately concludes that the past cannot be changed.
 * Strangely enough, this trope is seen in the original, Final Fantasy I. The story begins when the Light Warriors are sent to the nearby Temple of Chaos to kill the renegade knight Garland.
 * Shadow Hearts: Covenant ends with
 * And this raises the question of where Anne's Cross came from.
 * In the good ending,, he sends himself back to the beginning of the first game. As he waits for the train, there are hints that
 * Regarding that good ending, Yuri actually.
 * Soul Nomad and The World Eaters features one of the most bizarre examples of this trope: During an early cutscene during a New Game+, possession of a certain item causing the fall of  that is a part of your own timeline's backstory  Thus, the alternate timeline version of you two not only set in motion the events of the main story and, but also become two of your own worst enemies, and get killed by yourselves. Whew.
 * Not only bizarre, but also Squick of possibly  overlapping with  /HoYay. In one of the ending where you play as the heroine, you basically travel the world together with , romance subtext included. It's still vague whose soul becomes whom (fans generally assume Gig became   while Revya became  , but another theory is that   waited the two souls to fuse together before splitting them apart. So you get either you romancing a half of your reincarnated alternate-dimension self or you romancing your reincarnated alternate-dimension partner, but you can call him Gig. But, hey, at least it proves that even Gig can love!
 * The Jak and Daxter series is basically one big stable time loop, with the first two games being both prequels and sequels to each other. At the end of the first game, Jak discovers a huge portal through time. When activated at the start of the second game it unleashes the Metal Head race into the world, and Jak and Daxter are immediately sent to the distant future.
 * The vehicle they used to ride through the huge portal was created by  based on the specifications of the vehicle she found in the past -- which is the vehicle from the future.
 * The end of the second stage and the beginning of the eighth stage of Gradius V are both set in the same timeframe and same battleship, with the past and present versions of the Vic Viper running through segments of the stage alongside each other. The game records the actions of your 'past' version to replay in the second run-through.
 * Time Splitters: Future Perfect had numerous examples of this. One of the earliest examples is also one of the most memorable - you are given a key by your future self that you need to progress, and later pass the key on to your past self, leaving its initial existence unexplained.
 * As well in the You Genius U-Genix, when you find Dr. Crow, Cortez Cortez then shouts "DAMMIT!" at the top of his lungs, having it be loud enough to transcend time (he is in 2240, and it is heard in 1960 by Harry Tipper).
 * Sam and Max Season 2 has the player create at least two stable time loops. The first involves The other time loop involves
 * Then, in Season 3, Sam and Max have to use the astral projector from the Devil's Toybox to alter the actions of their ancestors Sameth and Maximus, to get the Devil's Toybox from Egypt and into the basement where they found it. The only way Sameth and Maximus did it in the first place was with information they wouldn't know at the time; not getting the box would probably destroy the universe.
 * There are other things. How do you know that the vampire elf needs to bite Jurgen the Vampire Hunter in the past? Because you've met Jurgen before in the present, as a vampire.
 * The Infocom Adventure Game Sorcerer features a Stable Time Loop. At one point, your future self appears and gives you the combination to a locked door, and demands your spell book. After you've unlocked the door, you have to travel back in time and give the combination to your past self, and get the spell book from him. (You can't carry anything with you when you go back in time.) The time travel spell is named "golmac" as a Shout-Out to the "gold machine", the time machine in Zork III. It's fun to do silly things like screaming or singing when your future self appears, then watch how they're described when it's your past self doing them.
 * Its sequel, Spellbreaker, features a two-in-one: you have to establish two Stable Time Loops in two different locations (with time limits on each), or else be wrung from existence by the ensuing paradox should you try to leave the hourglass. Early on in the game, you find a magic zipper that functions as your Bag of Holding; going back to that location in the past, you find a sack in its place, and have to swap the two (and all the contents thereof) before the rising water kills you. Elsewhere, there's a disused cell containing a moldy spellbook, entirely illegible save for one useful spell; when you return there in the past, you have to put your spellbook where you found the moldy one in the future (memorizing as many spells from it as you can first!) and leave the room precisely as it was (or will be) before the guards arrive.
 * The DS game Time Hollow is rife with these, mostly because
 * In all reality, The entire game is one BIG Time Loop which is both stable and constantly shifting. The overarcing plot is one huge Stable Time Loop but the events of both the past and present during certain periods is in constant flux, even though due to the looping nature, that flux is always in its own stable loop.
 * Near the beginning of Tomb Raider: Legend there is a flashback to Lara's childhood in which she set off an ancient device. Her mother then pushed Lara out of the way, looked into a ball of light and had a confused conversation with a mysterious figure (who the players can't see or hear) before disappearing. At the end of the game Lara inadvertently opens up a time portal and it is revealed that she was the person her mother was talking to at the start.
 * In Vandal Hearts, the NPC is sent back in time, and is then revealed to be the party member, who had Easy Amnesia until that point. The loop aspect comes in with the character's pendant, given to the earlier version by the later version.
 * This trope is brought up tragically in Wild Arms 5, where it is revealed that heroine is stuck in one of these. She is forced to continually travel 1,000 years into the past to set in motion the events of the game... but not before she sets herself up to awaken during this time period so she can ensure things play out how they should, and she is sent to the past once again. She can never leave this loop, as it may have cataclysmic consequences, and she'd much prefer her beloved to be happy. Although all the traveling and slumber gives her Laser-Guided Amnesia, she always remembers everything before she makes her Heroic Sacrifice.
 * The plot of Taiyou no Shinden Asteka II (a.k.a. Tombs and Treasure) is that the player characters are searching for Professor Imes, who went missing while exploring the ruins of Chichen Itza. One of the ruins is "The Tomb of the High Priest". The ending reveals that.
 * An unusual example in Okami, where the protagonist's past self, Shiranui, travels to the future.
 * The indie game Original War is all about this, with the Americans and Russians sending soldiers into the distant past to fight over the game's Phlebotinum. Whoever wins the war keeps the Phlebotinum, but near the end of the Cold War the losers send a strike force back in time to steal it...
 * The Infocom Interactive Fiction game Trinity contains both a major and a minor loop. The minor one involves an umbrella lost by a woman in London that you retrieve; when you go back in time to just before the bomb is dropped on Nagasaki, you give the umbrella to a girl, who will grow up into the woman you met in London.
 * Chrono Trigger's entire plot is concerned with a bunch of stable and unstable time loops. One that carefully averts the paradox element is when . This is not a paradox because they don't alter what anyone in the past witnessed and so don't inadvertently cancel their own actions. Most of the other time loops are not resolved so immaculately. Needless to say, this causes problems.
 * Sunset Over Imdahl, a freeware game made with RPG Maker, contains such a loop
 * In Bookworm Adventures Volume 2,
 * In City of Heroes, the Menders of Ouroboros are a time-travelling group dedicated to keeping the timestream straight. The first one you meet accidentally creates a Stable Time Loop when he rambles on about how you and he solved a problem in a mission you haven't undertaken yet.
 * Xenosaga:
 * Present in the OEL Visual Novel Mirai Imouto. Misaki travels from the future to the present,
 * In Final Fantasy Legend III the party is warned by their Elder that people in the Past are looking for the Talon Units. In said Past they meet the said Elder and ask where they can find Talon Units. Past Elder also is thinking about naming a town and asks for a name.
 * In the first Breath of Fire,
 * Chzo Mythos: The Man in Red's reason for existing is to ensure reality maintains a stable time loop.
 * In Blaz Blue, the attack of The Black Beast in 2100 A.D. nearly destroyed the world until Nox Nyctores weaponry was developed to fight it. Then in 2199 A.D. One of these Nox, Murakumo fuses with Ragna The Bloodedge, creating The Black Beast, which is pulled back in time to 2100 A.D.
 * The other half ot the Black Beast is equally paradoxical: The Black Beast's existence requires the fusion of Ragna and Nu's Azure Grimoires. Ragna's Azure came from
 * In the prequel novel Phase 0 it's revealed that
 * An odd example from Final Fantasy Crystal Chronicles Echoes of Time:
 * The key to Karazhan used by players in World of Warcraft is acquired when they perpetuate a stable time loop centered on an object. After collecting the fragments of Khadgar's broken key, they take it to Medivh to be repaired. Medivh cannot immediately repair it and so instead gives the player a spare; the key he is repairing will be given to Khadgar to be broken in the future and collected by the players to be repaired by Medivh yet again.
 * The entire point of the quests in the Caverns of Time is to ensure that time remains stable. The Infinite Dragonflight are doing their best to change the history of Azeroth for their own ends and it's up to you to stop them. Canonically you are victorious and their efforts are ultimately futile.
 * There is a quest in the Dragonblight where Chromie sends you to Nozdormu's shrine to help him against the Inifinite Dragonflight, and during the fight, your future self appears to help you. The next quest is to go back and fight that same battle again, this time with you helping your past self. Don't ask how it's supposed to work out if you choose to complete the first quest but not the second...
 * "No wonder I started drinking."
 * In Dragon Quest V:
 * In Runescape, this is part of how the quest "Recipe For Disaster" works. Specifically, in the Evil Dave subquest, when you have to make various soups, then have Dave taste-test them, even though to his perspective, the events of the quest happened earlier. When you step into the time-field to give Dave his soup, the player tells Dave specifically to remember how it tastes.
 * In Spellforce
 * There seems to be one in The Witcher:
 * In Nine Hours Nine Persons Nine Doors, this is one possible interpretation of the ending:
 * In Do Don Pachi DaiFukkatsu,
 * In Bastion, activating the Bastion's Restoration Protocol rewinds time. Fridge Horror sets in when you realize how many loops it might go (or have been) through before something could change and lead to The Kid activating the Evacuation Protocol instead.
 * No time to explain You are watching tv when yourself from the future, with armor and a laser gun, bursts through your wall. He is dragged away by a giant lobster, and drops his laser gun. You use it to save him. When you defeat the giant lobster (and included alien mothership),
 * Escape From St Marys: Your explorations from the school reveal various cases of vandalism. When you go to the past, you turn out to be responsible for every one of them.
 * No time to explain You are watching tv when yourself from the future, with armor and a laser gun, bursts through your wall. He is dragged away by a giant lobster, and drops his laser gun. You use it to save him. When you defeat the giant lobster (and included alien mothership),
 * Escape From St Marys: Your explorations from the school reveal various cases of vandalism. When you go to the past, you turn out to be responsible for every one of them.

Web Comics
"Thief: Well. I deserve this.
 * This Questionable Content guest strip. VERY SPOILERIFFIC!
 * In the Dominic Deegan, Oracle For Hire arc "The Storm of Souls", Dominic researches the creation and death of the first Acibek at the advice of Klo Tark, who met Dominic for the first time when he saw him several thousand years ago watching the death of Acibek.
 * These happen so often in Bob and George that characters declaring "I hate time travel" became a Running Gag.
 * In Wicked Powered, time travel incidents result in the protagonist being his own father AND his own mother.
 * In Stickman and Cube, Cube purchases a time machine on eBay. The time machine then travels to the future by itself, and when it returns, Cube sends it back. Through time. To before they bought it. The guy who sold them the time machine finds it, and, having no other use for it, puts it on eBay...
 * In probably one of the shortest and most succinct versions of the trope, Fuzzy of Sam and Fuzzy engages in a Stable Time Loop in this strip.
 * Not quite as short as this one from 8-Bit Theater where Black Mage witnesses himself saying something in the future, wonders out loud why he will say it, and then says it in response to Red Mage's explanation in the space of three "panels". In the following strip, Red Mage raises the question of where these words are actually coming from. "Information cannot erupt into being from nothingness! It's a paradox!"
 * Equally as short is this Faulty Logic page, on why you shouldn't rob your future self.
 * Here's another 8-Bit Theater example. In a previous comic, . In the linked strip, the other three Light Warriors  Thief remarks on how that "worked out okay." Cue

Sarda: What you deserve is so much worse."

"Sarda: No one can unmake the past. It's already happened, there's no "undo". Similarly, the future already happened. we just haven't reached it yet.
 * Eight Bit Theater is revealed to be one giant time loop. Here's how it goes;  As Red Mage points out, Sarda is just as responsible for his suffering as they are, as he could have stopped them beforehand. He retorts with;

Black Mage: Okay, I have a theory. It's called: I never knew it possible to care less about time travel."

"GC: "L1ST3N TH3 UN1V3RS3 W1LL 34T P4R4DOX3S FOR BR34KF4ST... G3T US3D TO 1T""
 * The Space theme of Irregular Webcomic was stuck in one complex Stable Time Loop in which the characters constantly revenge their own actions to themselves. It ended taking up most of the other themes, and (as expected) ended in a Rocks Fall, Everyone Dies at the end of that year.
 * Of course, parts of the time loop were unstable, as Iki Piki's Splanch is now, theoretically, infinitely old.
 * This Starslip Crisis strip is utterly shameless and straight-faced about this trope. When strips had individual names it thanked Heinlein
 * The entire Surreptitious Machinations story arc of General Protection Fault was ultimately about stopping a Stable Time Loop that a tyrant was using to stay in power.
 * Occurs in Sluggy Freelance during the Story Arc, thanks to a godlike who decides "Life's SO much funner with the paradox rules turned off!"
 * The ultimate fate of  in The Adventures of Dr. McNinja,
 * Every instance of time travel in Umlaut House.
 * It's pretty safe to say that the majority of the plot of Homestuck is built out of Stable Time Loops, both intentionally and accidentally created. To describe all of them would probably take up most of this page.
 * See the Weird Time Shit page on the MSPA Wiki (massive spoilers). The most prominent examples being and
 * Best of all, the latter actually leads to the former. After And best of all? The
 * Best of all, the latter actually leads to the former. After And best of all? The

"Adam: Oh, no! I hate time travel."
 * To clarify:
 * A more minor example, which still emphasises the nature of Weird Time Shit, is when Present-Karkat is on his bulletin board, having an argument with Future-Karkat. Eventually Future-Karkat logs off, having left Present-Karkat in precisely the right state of mind not to take any crap from Past-Karkat when he logs in. (Not only that, but Present-Karkat changes his typing colour from grey to candy-red to make a point because Future-Karkat is "already" doing it.)
 * Meimu, the Big Bad of the "Rethinking the Natural Law" arc in Touhou Nekokayou, creates one by accident when trying to Set Right What Once Wasn't All About Me.
 * Bob and George Information ontological paradox causes one here.
 * A major one in Two Evil Scientists occurs when Tails attempts to
 * Shelly of Wapsi Square managed to take advantage of time loops and places where time flows in different directions to arrange the Vision Quest gone wrong in her childhood that had a huge influence on her character.
 * Lampshaded in The Omega Key when the characters discover that they themselves, via time travel, were responsible for the destruction that they thought they were wrongly accused of.
 * Shelly of Wapsi Square managed to take advantage of time loops and places where time flows in different directions to arrange the Vision Quest gone wrong in her childhood that had a huge influence on her character.
 * Lampshaded in The Omega Key when the characters discover that they themselves, via time travel, were responsible for the destruction that they thought they were wrongly accused of.

"Fox: That's like the eighth time that's happened!"
 * This probably happens in this Girl Genius strip. The time window that Bang sees the first time happens after the second one from the point of view of the characters in the window. Gil calls Bang a maniac in the first one, probably because she pointed a gun on them in the second one, which she did because "earlier" he insulted her.
 * Faulty Logic: Fox travels to the future to steal a comic idea from his future self. When he gets back, his past self snatches the page out of hand and disappears.


 * Then there was the time he built a time machine for the sole purpose of going back in time to stop himself from building a time machine, because he knows he'll end up building a time machine and misuse it.

Web Original

 * This is essentially one of Dr. Insano's backstories as part of The Spoony Experiment: Insano is an alternate-universe version of Spoony, who has grown so angry with the Final Fantasy franchise that he wants to go back in time to erase it from existence. Since being able to travel through time would require him to study science for decades, he decides to create a time loop just like that of the original Final Fantasy by studying science, travelling back in time and then obtaining all the knowledge he needs from his future self.
 * In Red vs. Blue, Church creates an uncountable number of Stable Time Loops as he fails his objective each time and keeps trying.
 * Local Cloudcuckoolander Caboose makes the following unintentionally profound statement when Church talks to him about his experiences with the timeline: "Time LINE...? Ehh, time isn't made out of LINES. It is made out of circles. That is why clocks are round!"
 * In Illo Tempore contains at least two stable time loops across four millennia.
 * The Flash game No Time To Explain. Your character is chilling at home when a future version of himself appears out of thin air, warning you of imminent danger. Seconds later, a giant crab grabs him and carries him away, leaving you to use his weapon to save your future self. After defeating the crab,
 * Robutt a robot is trapped in a time loop wherein it constructs itself out of junk, sacrifices its battery to power the new version, which gets in a time machine and goes back to do it again.
 * A Very Potter Sequel features a Stable Time Loop within a Stable Time Loop -- an impressive feat for a stage play.
 * In We Are Our Avatars, Komatsu and the others teach a few of their moves to a younger Toriko, setting Toriko's path in becoming a great Gourmet Hunter. In fact, Toriko learned his Knife and Fork techniques from Grey Fullblaster

Western Animation

 * The 2011 time travel Story Arc in The Packrat explains why Buchla modular synthesizers have no keyboard: Packrat scared and angered Don Buchla and destroyed his synth prototype with his time machine keytar.

Western Animation
"Goliath: If I didn't fear the damage you'd do to the timestream, I'd leave you here.
 * In Duck Dodgers, the queen of Mars finds out the one moment in his life that inspired Dodgers to become the person (or duck) he is, and sends Marvin the Martian back to prevent it. When he arrives, though, he finds that Dodgers was just a waterboy then. Refusing to believe that they were wrong, Marvin tries to make it happen the way it did, and fails his mission to stop it in the process.
 * In Futurama's episode "Roswell That Ends Well," Farnsworth is very adamant about not changing the past, unless of course it turns out they were supposed to change the past, in which case, they must, for the love of God, not not change it. Fry end up killing his grandfather Enos by mistake, after an attempt to keep him safe. He impregnates his grandmother, thus becoming his own grandfather, which becomes Chekhov's Gun. After that, Farnsworth gives up about not changing the past. The crew blasts up Roswell Air Force Base, steals some gear, rescues Zoidberg and Bender's body, and blasts off into space. Farnsworth then delivers one of the best lines ever: "Choke on that, causality!" Oh yeah, and throughout all this, the crew ends up being the mysterious alien ship that crashed in Roswell, and Zoidberg is the alien.
 * Later, the aforementioned Chekhov's Gun comes into play, which gave him a birth defect that enabled him to fight the Brainspawn. He ends up trapping himself with the Brainspawn, and they send him back in time, so he can avoid falling into the cryogenic tube, and live out his life in the 2000s. It turns out Nibbler is the reason he fell (Nibbler never went back in time, he's just that old). Nibbler convinces him to stay by saying he might have a chance with Leela in the future, and thusly helps himself fall alongside Nibbler. In a clever twist, on an earlier flashback episode, you can see Fry and Nibbler's shadows just as Fry falls into the tube.
 * If you look carefully at the pilot episode when Fry puts down I.C. Wiener's pizza on the crygenic lab desk, you can see Nibbler's eye poking from under the desk. Yes, the writers planned that far ahead.
 * Bender's Big Score adds a few more. The aliens that destroyed civilization in the background while Fry was frozen? That was Bender gone back in time. Fry's dog turned out to have a happy life with a copy of Fry who chose to stay behind in the 2000s, while letting his other copy freeze to the year 3000. He gets killed and instantly fossilized when a mind controlled Bender blasts Fry's apartment.
 * Also, in the movie, their main method of time travel, the ball, is stated to be a self correcting method. Thusly, any copies made using the time travel are doomed to die horribly at some point. Some last longer than others. Farnsworth and Nibbler state that there can't be any paradoxes, and if there are, such as by the end of the movie where it's revealed there's hundreds of Benders, it rips open a hole in the universe, leading to the events of the second movie.
 * The Game actually had.
 * In an episode of Mary Shelley's Frankenhole
 * Time travel in Gargoyles (via the Phoenix Gate) can't be used to change the past - no matter what you do, You Already Changed the Past. But if the plot requires it, you can turn yourself into a god by means of a Stable Time Loop. The Avalon arc includes the flashback antagonist known as the Archmage in a classic bootstrap scenario: he travels back in time, saves himself from his canonical death at the bottom of a cliff, spends a day jumping through time handing his past self an absurd amount of firepower, ending the day by sending his past self off to repeat the process.
 * Magnificent Bastard David Xanatos uses this to his advantage in "Vows". When pulled to 975 AD, he gives the Illuminati a coin to hold onto for one thousand years, and then deliver it to a young David Xanatos. The coin wasn't worth much in the past, but by the time it reaches him in 1975, it's worth twenty grand, which is the foundation for his fortune. He also gave them a letter to hold onto for 1,020 years, so he'd get it precisely one week before the episode began, telling himself exactly what to do. He makes a direct Lampshade Hanging of the trope when Goliath arrives to rescue him.

Xanatos: But you won't. Because you didn't. Time travel's funny that way."


 * Goliath found out that history is immutable to his dismay in the same episode. He tried to convince teen Demona not to turn evil. It worked, but only temporarily.
 * In the same scenes, Demona always knew history is immutable because she already saw it. Future/Present Demona was the one that brought them all to the past in that episode, and then she goes to her younger self. She travels 20 years into the then-future, to 995 AD, and Goliath catches a ride. She shows herself the slaughter of Wyvern castle, that all her rookery mates are dead, and then tells herself to get rid of all the humans. Initially her past self rejects this, and she fights herself. She at first seems to reject what her future self told her, and embrace what future Goliath told her as she is returned to 975. However, by the time those twenty years pass, she makes a plan to do exactly what her future self told her to do, eliminate all the humans from the castle. This causes the scene her future self used to scare her in the first place, resulting in the classic irony this trope generally causes. Future Demona wasn't actually trying to change it though, as she remembered what happened to her past self that night, and knew what would happen, it was all a trick to turn herself evil and turn her into the person she becomes.
 * The final irony of this is that young Demona was simply told "the humans" destroyed our clan. She assumed it meant the humans in the castle, and tried to get rid of them by allowing the Vikings to sack the castle. In reality, it was the Vikings who killed the gargoyles, so this became a classic case of fulfilling a prophecy by trying to stop it.
 * The episode "M.I.A." hints at what could be a possible out within a Stable Time Loop: . Or fate could just have been screwing with him to achieve the predestined result.
 * The Star Trek the Animated Series episode "Yesteryear" has Kirk and Spock return from a trip to the past to find that the ship suddenly has a different science officer, and no one else knows who Spock is. Spock relates a memory from his childhood when his life was saved by an adult Vulcan, who he realizes looked exactly like he does now. So he has to take one more trip to the past to save himself and set things right.
 * The Powerpuff Girls: Mojo Jojo goes back in time to try to kill Professor Utonium as young boy to prevent him from creating the Powerpuff Girls. The girls follow and save The Professor, and it was this very incident that inspired him to get into science and try to create "the perfect little girl."
 * The Fairly Odd Parents full-episode special "The Secret Origin of Denzel Crocker": Timmy goes back in time to figure out why Crocker is so miserable. He discovers that Crocker had fairy godparents as a kid, and not just any random fairies, either--Cosmo and Wanda were his fairies. Since present-day Cosmo and Wanda had no memory of this, they quickly figure that Crocker had done something to lose his fairies. They then set out to try to stop this, but Timmy ends up being the one revealing Crocker's secret in public. Worse still, he leaves A.J.'s "Crocker-tracker" in the past, which Crocker managed to reconfigure with Cosmo's DNA, making it a much more effective "Fairy-Finder" than the one present-day Crocker previously had.
 * ...which actually proves to be only a semi-stable time loop. If it were a true stable time loop, Crocker would have had AJ's tracker the entire time. Either that, or he 'forgot' that he had it until immediately after Timmy gets back from his time-travel.
 * And the reason Cosmo and Wanda didn't remember having Crocker as a godchild? The past Cosmo was playing with the device Jorgen Von Strangle used to erase young Crocker's memories of having fairies (the device being a reference to Men in Black) and accidentally erased his and Wanda's memories of having Crocker as godchild.
 * Transformers Generation 1 featured a truly epic multi-layer time loop revealed over the course of several episodes. 11 million years ago, A3 led a revolt against the Quintessons; however, in 2006, the Quintessons yanked A3 into their own time to prevent themselves from losing Cybertron. Blaster, Perceptor, Blurr, and Wreck-Gar go back in time to help the rebellion, while the Aerialbots save A3 from the Quintessons. A3 returns to his own time to lead the rebellion. Two million years later, A3, now known as Alpha Trion, meets the Aerialbots, who have travelled back in time from 1986. The Aerialbots persuade him to save the life of a young dock worker named Orion Pax, who he rebuilds into Optimus Prime (and also rebuilds Orion's girlfriend Ariel into Elita One). The Aerialbots return to their own time and then, in 1984, Optimus Prime and Alpha Trion build the Aerialbots from a group of shuttles. You may wish to draw a diagram.
 * In the Pinky and The Brain episode "Brain of the Future," the two mice travel to the distant future in a time machine given to them by their future selves, who had just returned from the distant future. There, they lose the time machine they arrived in but manage to steal a "different" one and return to give it to their past selves...
 * Kim Possible: A Stitch in Time has this. Shego stole the time monkey only because she stole it, went back in time, transferred Ron away from Kim, and then told herself to steal the time monkey. This somewhat changes when the time monkey is is destroyed and the entire timeline that its use created is revoked, along with the very existence of the time monkey. So, you destroy it once, it erases itself from ever existing. So Shego never went back in time, Ron never left KP, and nobody ever knew or cared about the time monkey.
 * And within that wheel, Shego takes the monkey while in the past and escapes into the timestream, so Kim goes straight from the past to face Shego in the Bad Future. Shego manages to Take Over the World partly because Kim wasn't around to stop her, since she skipped over that whole time.
 * On the other hand, the self-destruction of the time monkey is only implied; if its destruction doesn't affect its past existence, then the movie becomes a case of the Timey-Wimey Ball.
 * The Dexters Laboratory movie "Ego Trip" had this going on. The movie starts with robots appearing in the lab, looking for "the one who saved the future" and attacking Dexter. Inspired by this, Dexter hops in his time machine and ends up going on an adventure with three future versions of himself, battling four Mandarks. In the end, the day is saved when Dee Dee walks in and does her thing Furious at being upstaged, the four Dexters build some robots and send them to beat up "the one who saved the future". When he realizes this, Dexter's reaction is to give up on explaining time travel and then going to eat lunch.
 * The only time time travel occurred in SpongeBob SquarePants had Squidward going to the distant past through a series of events stemming from avoiding Spongebob and Patrick trying to get him to go jellyfishing with them. He meets the caveman versions of them and shows them not to be afraid of jellyfish by demonstrating jellyfishing, then giving both nets to try it themselves. Upon his return, he mocks whoever was the one who invented jellyfishing, to which Spongebob and Patrick tell Squidward it was him.
 * The Penguins of Madagascar episode "It's About Time" involves a time-traveling Kowalski trying to Set Right What Once Went Wrong while avoiding Temporal Paradox...  Hilarity Ensues.
 * The intro short for The Simpsons theme park ride has this. Professor Frink learns that Doc Brown's Future Technology Institute was bought out by Krusty the Klown and closed down, and uses the DeLorean to go back in time and prevent this. When he arrives, Frink accidentally runs down the investor to whom Doc was speaking, forcing him to sell the Institute to "that mercenary clown".
 * Teenage Mutant Ninja Turtles 2003 notably in "Timing is Everything".
 * In Teen Titans the time-travelling villain Warp thinks he's taking part in a Stable Time Loop; he goes back in time to steal a special clock because, a hundred years in the future, the historical records say that he went back in time to steal it. Unfortunately for him, the Teen Titans prove themselves able to Screw Destiny and stop Warp from stealing the clock, wrecking the time loop.
 * An episode of Family Guy explicitly pointed out the trope when Stewie and Brian accidentally caused the Big Bang due to time travel.
 * In the My Little Pony Friendship Is Magic episode "It's About Time", Twilight Sparkle comes across her (very badly injured) future self, who came from next Tuesday morning to give her a very serious message, but Twilight keeps interrupting her future self, until she gets sent back to the future before she could finish her warning. Present Twilight spends the next several days worrying about averting impending doom and getting more and more injured because of random events, matching up her future self's injuries  which is when Twilight decides to use a special magic scroll to go back in time and warn her past self that nothing bad was going to happen and she had no reason at all to worry about.
 * In one episode of Justice League Unlimited, Braniac 5 summons Green Lantern, Green Arrow, and Supergirl to the 31st century to help in a conflict as history records show that the three time-traveled once- but Supergirl didn't return, implying that she died. At the end

Real Life

 * You never thought you'd see it, but some non-trivial physicists are wondering aloud whether the future is actively trying to scuttle the LHC research project. The string of mechanical difficulties, they say, may be more than mere chance: Whether through [future] human intervention or the universe itself exercising some form of upstream-acting Ontological Inertia, the future is trying to make sure we don't mess with Higgs Bosons. Loopy? Literally. Crazy? Probably. Impossible? Well...
 * Mumbo? Perhaps. Jumbo? Perhaps not!
 * In terms of the theory of relativity, time travel would take the appearance of a closed timelike curve, which is a series of events returning to its starting point - such as time travel returns to the past. That leads to the inevitable paradoxes, but some solutions claim that if time travel is possible at all, it's only possible in a stable form: the only form of time travel possible generates a Stable Time Loop.
 * While that may seem supremely useless - what good is a time machine if it can't change anything? - that's not really true. A computer that could only build Stable Time Loops could run algorithms like "open time communication channel to 5 minutes into the future, receive answer from future, close channel, check answer (which takes 5 minutes in this example), if correct, send answer over the communication channel that was now just opened, if incorrect send different answer to past over the same communication channel", and then consistency would force the algorithm to return the output to some given puzzle. This is known as Time Loop Logic. Receiving an incorrect answer from the future would cause a paradox, and thus is impossible. Therefore either the answer will never arrive, or you will have created an ontological paradox, fabricating the answer from nowhere. The step of checking the answer is required for the algorithm to work.
 * Less esoterically/more science-fictionally, a time machine that can't change anything would also be just dandy for observation, thanks. (Better, really, since you don't risk stepping on the Butterfly of Doom.) Video from 20,000BC anyone?
 * There is apparently a theory out there that human time travellers seeded the young planet Earth with life. This is sometimes known as the Completely Ridiculous Anthropic Principle.
 * Older theories of cosmology fiddled with the possibility this universe is a Stable Time Loop. Big Bang leads to Expansion, Contraction, finally the Big Crunch which Big Bangs again and we still have no idea where it all 'originally' came from.
 * Some theories of particle physics hold that antiparticles (particles with the opposite charge and parity of a "standard" particle) travel backward through time. It's also widely believed that particle-antiparticle pairs randomly pop into existence from the Quantum Foam, and then feel their mutual attraction and annihilate each other moments later. It's also possible to see this as a single particle traveling in a loop through time: Forward as a regular particle to annihilate with its antiparticle, then backward as its antiparticle to annihilate with its standard particle, and repeat.