Dead Pet Sketch

Someone has to take care of someone else's pet while the someone else is away. The pet ends up dying (through carelessness, though sometimes just an accident or through bad luck). The caretaker often ends up buying a replacement and trying to pass it off as the real thing. Sometimes this works great, but in most cases, the owner isn't fooled for one second, as they instantly notice changes in the pet's behavior and appearance (or even the sex, for particularly clueless caretaker).

Sometimes the pet in question is not actually dead, just missing, in which case The Reveal often centers around the substitution succeeding until the real pet turns up. Either way, the caretaker will have some explaining to do.

Not to be confused with Monty Python's "Dead Parrot Sketch", which is an altogether different beast entirely... in which the Norwegian Blue Parrot was... resting. Here is an external link to that sketch.

Done so often and often so miserably that it seems to have finally, mercifully become a Discredited Trope.

See also Broken Treasure and Of Corpse He's Alive. While many examples of this trope involve a replacement goldfish, they generally do not involve the Replacement Goldfish.

Anime and Manga

 * In .hack//SIGN a girl PC asks Tsukasa to take care of her grunty (a small, pig-like virtual animal) for a couple of days while she's away. The grunty gets sick (or apparently, was already sick and she didn't notice it) and dies despite Tsukasa's heroic effort to find a cure (in a very cold place, and he's the only one who can feel the cold). He doesn't try to lie.
 * A very similar scene occurs in .hack//Legend of the Twilight, but the grunty lives (and its owner is admonished for the irresponsibility of palming it off on someone else when it was sick).
 * In Kiki's Delivery Service, Kiki is supposed to deliver a plush cat, but she drops it along the way. She ends up substituting her cat Jiji (who happens to be a dead ringer for the plushie), who has to act like an inanimate object until she can retrieve the real thing and deliver it.

Film

 * A The Three Stooges short features Moe, Larry, and Curly trying to cover up the fact that their animal hospital misplaced a valuable poodle, ending up finding a lame replacement until they can rescue the dog from dog-nappers.
 * Meet the Parents with a cat. To clarify, the cat ran away and Greg spraypaints a stray to look like the escaped pet. The stray tears up everything in the room, including the bridal gown.
 * Bolt, when
 * The Russian 1995 movie "Moscow Vacation" features the "Dead Dog in the plane" story below.
 * A driving force behind the plot of the movie Toy Story 3, in which this is the exact reason why the Big Bad became that way.
 * In the Film of the Book Patriot Games Jack Ryan makes a call home to tell the house keeper to check on Sally's gold fish, and if they're dead, to get new ones. When she gets home Sally is amazed by how much her gold fish have grown while she was away.

Literature

 * A throwaway line by Susan in Hogfather implies that she has successfully pulled the pet-replacement trick on Twila at least once, with gerbils. Presumably Twila herself was the one who discovered the deaths of the three that are buried in the garden.
 * By Thief Of Time, Susan has evidently gotten tired of playing out this trope, as she chooses stick insects as the new class pet because it's hard to tell if they are dead.

Live Action TV

 * Home Improvement, with a goldfish
 * Diff'rent Strokes, Arnold's goldfish, Abraham
 * Saved by the Bell, with Slater's chameleon
 * Better with You, where Vicky and Joel adopt Mia and Casey's cat and then lose it
 * Traffic Light, with a stuffed dog named CJ that Adam won for Callie
 * Inverted in Malcolm in the Middle, where Dewey is promised a dog if he can take care of a goldfish. His parents, not wanting a dog, replace the live goldfish with a dead one. Only for Dewey to walk in the next morning with the goldfish still alive.
 * Lampshaded in The King of Queens, where the dog Doug's had from childhood dies and his family scrambles to replace it.
 * Only Fools and Horses twisted this beautifully when the main characters replaced the canary only to have the owner very surprised on her return because it had died the night before.
 * A twist that is also the entire basis of an urban legend.
 * Everybody Loves Raymond did this, with Ray accidentally putting Ally's hamster in the freezer.
 * On Taxi, Bobby fish-sits for Tony with predictable results. Tony seems happy and everyone is relieved until he says, "I hope they get along with George and Wanda [the original goldfish]."
 * The Cosby Show with a hamster. The little girl wasn't fooled for a moment as this happened every time she left her hamster with somebody.
 * My Wife and Kids, with the school's hamster. First, the family tries to convince Kady that he's just sleeping, then Michael buys a replacement. When the replacement has babies, they confess the truth; Kady is nonplussed ("I touched a dead hamster?! Eeew!!").
 * Scrubs did a unique inversion wherein Carla loses Turk and J.D.'s stuffed dog Rowdy.
 * Also a multi-season delayed Brick Joke,
 * Mork and Mindy, with a caterpillar. Turns out it was just transforming into a butterfly.
 * Northern Exposure: When Chris in the Morning runs over a woman's dog in "Nothing's Perfect" (4.3), he falls for and tries to court her... but ends up killing all her pets.
 * Kenan and Kel with Roger's (Kenan's Dad's) Cockatoo.
 * Averted in another episode where the guys housesit for Chris, and his goldfish is just about the only thing in his house that isn't destroyed by the end of the episode.
 * The Office subverts this somewhat, in that Dwight, while supposed to be caring for Angela's sick cat, intentionally kills it to put it out of its misery. He then tells her that it was dead when he got there. Naturally, the truth comes out and there is hell to pay.
 * In Mad TV's dead pet sketch, a housesitting friend is feeding the homeowner's pet parrot when it bites him and he flings it to the floor, killing it. He then goes on to kill the friend when he returns, the friend's mother, and several bystanders including the mailman and a jogger. But, of course, at the end we find out
 * Worst Week, the US adaptation of The Worst Week of My Life, had one episode which was entirely centered around this trope. The lead character feeds his in-laws' bird an avocado... unfortunately, it turns out that avocados are deadly for that kind of bird. So the lead character then buys a replacement... and, trying to avoid suspicion, carries it back in his pocket, leading to a rather awkward moment when the bird starts moving around. He manages to kill that bird too while trying, a bit too forcefully, to keep it quiet in his pocket...
 * The UK version has an hilarious arc in the first series in which Howard accidentally throws his in-laws' scottie dog into a cement mixer and is forced to find a replacement by the wedding day. Unlike most of the above examples, the in-laws are well aware of what happened to the dog.
 * Fresh Prince of Bel Air did this once with a rabbit belonging to Nicky. Hillary bought a replacement rabbit that looked nothing like the dead rabbit.
 * Just Shoot Me plays with this one when Finch asks Maya and Jack to watch his evil cat Spartacus. Jack accidentally kills it while chasing it with a remote-controlled car and feels horribly guilty. Finch, kept unaware of how his cat died, gets it stuffed and puts it in Jack's office in appreciation of the fact Maya and Jack are being so sympathetic. Insomniac hilarity ensues.
 * Played for Black Comedy in an episode of One Foot in the Grave.
 * WKRP in Cincinnati: Herb accidentally spray-painted his daughter's pet frog in one episode.
 * Shakey Ground (short lived Sitcom starring Matt Frewer): In-laws go to Hawaii for a week leaving their dog (which they inherited from the grandmother) with the family. Dog dies, dad gets a replacement from an animal shelter which looks exactly like the dead dog...except this one is female.
 * In Arrested Development GOB feels that he would be entitled to a full refund for the pigeon he accidentally killed then stuck in the freezer. The sketch itself happens offscreen, and we see GOB throwing into the sea in anger over their return policy. He does the same thing a week later with a rabbit.
 * The Golden Girls does this during an Empty Nest crossover. Dreyfuss runs away when Sophia is supposed to be watching him, and she gets a replacement lookalike. The real Dreyfuss then comes back, and the girls wind up with both of them, with Rose having to ferret out the real one before Harry gets home and take back the duplicate. It's indicated, though, that the wrong dog got taken back.
 * In an episode of Full House, Joey promises Michelle, who is traumatized over accidentally killing her pet fish, that the new one he bought for her is going to live for a long, long time. After she leaves, Jesse asks him what's going to happen if the fish does die, leading Joey to reveal an entire kitchen cabinet full of identical replacements on standby.

Newspaper Comics

 * Curtis did not take Michelle's demands for her spoiled cat seriously. When the cat became unresponsive, he didn't panic... until he learned that the closest thing at the pet shop was way out of his price range.
 * One Sherman's Lagoon arc had Sherman eating a neighbor's pet catfish. He tries to get a new to replace it, only to learn that catfish are a pain to deal with, and the neighbor hated the pet to begin with. He ended up stuck with the replacement, up until Megan found a recipe for cooking catfish...

Real Life

 * Real Life Example: The original Petra on Blue Peter died after only her first appearance. Pet shops were scoured to find a replacement, as it was felt to be to upsetting for viewers. It worked too, and no-one knew for years.
 * When Ronald Reagan was abroad for a meeting with the Soviet Premier, two of the goldfish in the house he was staying in died. He bought two more, leaving a note for the family explaining what had happened.
 * There's an old story about a woman who was flying on an airplane with her dog in a cage. She had forgotten something at home and left the dog with an airport official. The official noticed that the dog inside was dead. So he raced out and got a new dog that looked similar. When the woman returned, he gave her the new dog, and she knew right away that it wasn't her old dog. When he asked why, she told him that her dog was dead and she was taking him to his old home to be buried.

Theater

 * The driver of the plot in the play The Lieutenant of Inishmore. Padraic's cat Wee Thomas is killed by rival IRA thugs, and his father and neighbor spend much of the first act trying to find a replacement. They do, but he ends up shooting it when he finds out its not really his cat.

Video Games
"Strong Bad: Hey, it's the Laugh Trackalicious Adventures of Guy and Girlfriend! Oh, this is the one where Guy thinks he kills Girlfriend's hamster, and tries to replace it with another hamster, but the first hamster had been dead all along, so Girlfriend thinks it came back to life! And then...the hilarity...and the humour...and the original comedy television writing!"
 * Strong Bad refers to this trope in SBCG 4 AP Episode 1: Homestar Ruiner:

Web Comics

 * Sluggy Freelance Poor Frog still has no idea that his er ... girlfriend Corsica has been replaced countless times. The other members of Hereti Corp treat her as little more than a pet to be replaced in case one of them goes missing or dies. Interestingly enough the fate of the original is listed as 'unknown'.
 * Alternate reality Frog does not take the revelation well.

Web Original

 * In Episode 1 of The Dr. Steel Show, Doctor Steel announces that it's time to "Feed the Hamster" (a segment with its own musical intro). However he soon notices that the hamster has expired. After a brief moment of mourning (with accompanying sad violin music), he quips, "But it does mean that my experiment was a success!" before putting the body in a pneumatic tube and launching it off his island.

Western Animation

 * Rugrats, with a pillbug.
 * Played with in Phineas and Ferb - Baljeet is to watch Perry and make sure he doesn't run away. Because Perry is a secret agent, he manages (with much difficulty) to escape to perform his mission, as he does every day. Baljeet is convinced that he lost Perry and weeps incessantly. When Phineas returns, Baljeet is just about to break the news to him when Perry shows up and Phineas says "Oh, there you are Perry."
 * The Brak Show, Thunderclese's goldfish
 * Parodied in Rocko's Modern Life, where Filburt isn't broken up about the accidental death of his pet mynah bird because it was from an extremely short-lived species, and was going to die of old age soon anyway.
 * However, at the end of the episode, Filburt is quite shocked to find out the actual cause of death for the bird:
 * King of the Hill: While minding Hank's elderly bloodhound Ladybird, Luann mistook the dog's stubborn lethargy for death and, predictably, bought a new bloodhound to replace her. The presence of the second dog roused Ladybird into a flurry of activity, leaving Luann with the new problem of identifying the correct dog.
 * The Magic School Bus with a rooster.
 * The Fairly Odd Parents has an episode wherein we discover every time Timmy goes to summer camp, his parents are in charge of his pets. Since his parents' negligence is the reason Timmy has Fairy Godparents, you do the math. Hilarity Ensues when Timmy wishes that everything in his mum's garden were "filled with life," and all the pets who "ran away" come back as zombies.
 * Angela Anaconda with a turtle.
 * Lampshaded in an episode of The Simpsons. When Bart and Lisa go off to summer camp, Lisa tells the parents not to replace the pets if they die, because she'll notice.
 * Rather ironic, considering that the cat's been replaced four times. It just wasn't secret.
 * The "missing pet" variant was played straight in the Franklin episode Franklin and the Two Henrys. Beaver gets Franklin to look after her hamster, Henry. Franklin accidentally lets Henry escape from the cage. So, he gets a replacement hamster. Beaver returns, and then the original Henry turns up while Franklin tries to pass the other hamster off as Henry, Hilarity Ensues.
 * In the SpongeBob SquarePants episode, "I was a Teenage Gary." Spongebob leaves Gary in Squidward's care when he leaves, and Squidward immediately forgets about him. He doesn't try to replace him though, because he doesn't remember until Spongebob returns.
 * Also the episode "Wormy" where Spongebob and Patrick petsit for Sandy, and become best friends with her caterpillar, who turns into a butterfly the next day, but they think the butterfly is a monster that ate it.
 * An episode of Recess had the kids come back after a long weekend to discover that Speedy, the class hamster, had died. During his funeral, several older kids and even some parents turn up to pay their respects to their beloved class pet. Then someone pulls out an old class photo with Speedy in it, and everyone starts noticing that the details are wrong--Speedy's feet were supposed to be white, Speedy was supposed to be a girl, etc. Ms. Grotke awkwardly admits that since the teachers thought the students would be too young to know how to cope with death, they would secretly replace Speedy with a new hamster every time the old one died. As this has happened over 40 years, several of the older mourners then begin to realize that that's rather long-lived for a hamster.
 * In Fanboy and Chum Chum the titular characters have to watch over a digital pet for their friend, only to kill it. They decide to go bury it at the haunted Pet Cemetary, which makes it come back to life again! ...Only for them to accidentally kill it and bury it again several times.
 * My Little Pony Friendship Is Magic has a variant in the episode "A Bird In The Hoof"; it differs in that Fluttershy literally steals the Princess' pet bird in order to give it medical attention, and the drama lies in her caring for it adequately before giving it back to her. The bird dies at the last possible moment...
 * The Amazing World of Gumball actualy did this with Penny's pet spider.
 * Sagwa the Chinese Siamese Cat did this with a cricket.