Samus Is a Girl



"Kid Icarus: Gosh-a-cus, Princess Lana! Samus is super-duper-a-cus!

Lana: Well... Samus is a veteran of many impossible missions! Samus is a super-powered cyborg! Samus is the greatest space hunter in the Galactic Federation! [Samus removes her helmet] Samus is a... woman?!?!

Kevin: Whew! You sure are!"

- Captain N: The Game Master comic story "Money Changes Everything"

Bob is really in over his head, now! He's surrounded by more mooks than he could hope to defeat on his own. Suddenly, a stranger in full armor comes from nowhere and makes quick work of the whole lot of baddies. The warrior then turns to Bob, takes off his helmet and... holy crap! It's a girl! Alice arrives!

Samus Is A Girl is when an Action Girl is well established as heroic, or otherwise Badass before the first hint that she's female. Whether the initial lack of discernible sex is caused by bulky armor, baggy robes, subtler deliberate deceptions, shapeshifting, or even just the camera refusing to give a clear shot of any distinctly female parts of her, it's still Samus Is A Girl. Heck, a tank with a chick inside would count. Having a Tomboyish Name helps as well.

Oftentimes, Alice will only wear the form-concealing outfit during her introduction. Afterwards, it may end up getting lost or destroyed, and thereafter she wears something a little less ambiguous. Sometimes, she just stops on her own.

This trope is notably harder to pull off in some languages - those that don't use gender-neutral descriptors that much. (On the other hand, it's very easy to pull off with some foreign characters, since quite a few Japanese and African names can be assigned to either gender.) It's one thing to say Samus is a bounty hunter, but when your language demands that if the gender is known, this should be bounty huntress, characters that do know about Samus' gender and just don't care to elaborate to the listener couldn't just call her a bounty hunter without stretching suspension of disbelief. It's one thing to trick the viewers by clever terminology, but when you break your language to do it, the effect becomes not so much "Hey, that's right, the gender was never actually mentioned!", but "Um... so the character who was referred to as male by others who knew she was female all the time was actually female. Huh?".

See The Faceless. Contrast Unsettling Gender Reveal (where "Alice" turns out to be "Bob"), Sweet Polly Oliver (Samus Is a Girl from a viewpoint that already knows she's female) and Viewer Gender Confusion (where the audience, not the characters, don't know what gender Pat is). See also Geeky Turn On, which is sometimes related to this.

'''Spoilers Off. The fact the title of this trope gives an example is a pretty good reason why this trope should not be spoiler tagged, right?'''

Trope Namer

 * Named for Samus Aran from Metroid. In the first game, the player doesn't learn she's female until after guiding her through an army of alien baddies. Later games in the series still play with this trope. The Prime series, however, does not play with this, and gives her a rather feminine figure considering she's in armor. Other M completely throws away this trope, however, because you see Samus without her suit in the opening sequence, in many cutscenes (sometimes this is just a shot of her face through her visor), and in the death sequence.
 * The cheat code "Justin Bailey" entered in the first game, will start Samus near the end of the game, with no armor on.
 * The death sequences in Super Metroid, Metroid: Fusion, and Zero Mission also have her armor shattering and reveal her form underneath. Plus, Super Smash Bros Melee gives her a sleek version of the Varia Suit.
 * In the original game, even the manual refers to Samus as male. The developers only came to the decision to make her female about midway through the production process, when one of them casually remarked that it would be really funny to get to the end and discover she was a girl all along. Possibly one of the greatest instances of Throw It In in video game history.
 * The second game's manual, however, uses "she" throughout. A literal case of All There in the Manual, only confirmed by the best ending. (Later games do much the same.)
 * In Metroid: Zero Mission, you get a visor shot right before the game begins, but if you're not paying attention, you'll miss it. Hilarious, given that Zero Mission is a redone and updated version of the original game.
 * Naturally, this happens to our favorite Spartan in Haloid as well. Wait....
 * And it's not just in fan fiction! Canon Halo media uses the exact same trick not once, but twice - in the Halo Graphic Novel and  in Halo Legends.
 * Played with a little bit in Super Smash Bros. Brawl, if the player fights her as Snake on Shadow Moses Island. In his codec transmission, Snake remarks to Otacon that he's fighting "a woman in a power suit." Otacon is baffled as to how Snake can possibly know she's a woman. Snake's comments in this transmission, and in the one he makes if he fights her in her Zero Suit, are the main reason Snake/Samus has become a popular ship among the fans.
 * Hint: He figured it out by watching how she walks - and checking out the anatomy involved. This is a shout out to how the player finds.
 * These conversations may also be subtle foreshadowing of the Power-Suited Amazon Brigade that would appear in Metal Gear Solid 4 Guns of the Patriots. It's not the only thing Kojima foreshadowed in that game.
 * Also played with in Melee, where Samus's main trophy's description doesn't use any pronouns.
 * When Metroid first came out in the 80s, Nintendo USA ran a Metroid art contest in their magazine "the Nintendo Fun Club News" (a precursor to "Nintendo Power"). All the winners who had Samus unmasked in their art depicted her as a man.
 * This is the art in question. Notice the one that was tied for 4th. This was obviously based off an ending in the game, in which Samus' face was the only thing that was revealed. Thanks to the 8-bit graphics, it was STILL impossible to tell whether or not Samus was a girl. One could easily interpret that the person in the suit was simply a guy with Eighties Hair. Apparently, the artists settled for that notion. Seems that the judges of the art Did Not Do the Research and did the same. Either that, or Nintendo knew beforehand and decided to make the judges disqualify the entries that depicted Samus as a female in order to keep the twist ending a secret.
 * In the Captain N: The Game Master comic book, Samus was a regular character, and in her first appearance it surprised the regulars from the cartoon when she unmasked for the first time. The scene in question is quoted above.

Anime and Manga
"Ranma: Since when are you...
 * In the new Halo Legends anthology, the episode "The Babysitter" uses this trope for the SPARTAN sniper.
 * Which in turn is based off of one of the EU novels.
 * Marlene in Blue Gender. Yuji is her "Bob".
 * He's more surprised by the fact that she's human than the fact that she's female. Waking up in the middle of a Bug War and seeing nothing but Nightmare Fuel for a solid 5 minutes can do that to you.
 * In the "Battle Tendency" arc or Jo Jos Bizarre Adventure, Joseph Joestar and Caesar go to meet Caesat's mentor. When Joseph finally mets her, she is initially fully dressed and her face is concealed, and he thinks she must be a man... until she reveals her face.
 * Rei in the manga version of Neon Genesis Evangelion.
 * That is, when Rei's still inside the Eva. In the confusion of the battle, Shinji can't tell if anyone is inside the Eva (Rei's name comes up, but that seems to be a thought bubble rather than spoken dialogue on Misato's part). Shinji does cry out (in the English translation), "Our guy's getting clobbered!" But when he gets to NERV headquarters, he still seems to think he was saved by a robot. At any rate, as soon as the reader -- and, a few panels later, Shinji -- actually sees Rei, it's clear she's a Bandage Babe -- along with all sorts of other types of Fan Service / Fan Disservice.
 * Also worth noting: while the feelings that develops between Shinji and Rei are not entirely platonic, they never have any sort of outright romantic relationship either. Given Rei's origins, that would be all sorts of Squick.
 * Carefully averted in Rebuild of Evangelion 2.0 with Asuka, who arrives in Unit 02 to fight the Angel. Shinji had never seen her or her Eva before but when he does comment on the battle, he doesn't use any third-person pronouns in either the Japanese original or the English dub.
 * In Berserk Guts doesn't realize that Casca who is in full medieval knight armor is woman until he knocks off her helmet.
 * Later at a formal celebration Guts is approached Casca now dressed in, well, a dress, despite knowing very well that she's a woman, Guts is awfully surprised to see her looking like one, likely used to her being one of the guys.
 * Even later when the Hawks plan to  their guide is none other then Princess Charlotte who admits not realizing that she was a woman the first time they meet (much to Guts and Judeau's amusement).
 * When most people hear of the assassin Noir, the assume it to the be the codename for a male assassin, as opposed to the fact that it is actually two girls.
 * Especially ironic, since eventually it's revealed that Noir in fact originally referred to two female killers as long as thousand years ago.
 * In the Giant Robo OVAs, Action Girl / Cool Big Sis Ginrei first appears in disguise as a masked Badass Longcoat to rescue Dr. Shizuma -- for all of a minute, before suddenly changing into her trademark Chinese dress, and never using the "Iron Mask" disguise for the rest of the series.
 * Cagalli Yula Athha of Gundam SEEDs tomboyish personality and androgynous clothing originally fools both Kira and Athrun into thinking she is a boy.
 * Cagalli's gender confusion is also an in-joke to the viewers; Naomi Shindou usually voices young boys.
 * It doesn't help that all the characters in SEED have the exact same facial features, even across genders.
 * That'll be extradimension hit both for characters and Viewers, hence...because Only Six Faces rule we missed the part that Cagalli is Recolored Kira! and hence... Ship Tease
 * Cagalli is actually
 * In Ranma One Half, Akane exemplifies the trope when
 * A more handy example lies with Ranma's Unlucky Childhood Friend Ukyou. Having met her at a very young age, Ranma always believed her to be another boy; after a bitter grudge match in which she forced him to fight "seriously", he was stunned to discover she was actually a girl. Hilarity Ensues:

Ukyou: ...a girl? Since I was born, idiot.

(Ranma pours hot water on her)

Ukyou: Ow! Hot! Hot! Hot! (punches Ranma) Why the heck did you do that?!

Ranma: Hey, you didn't turn into a man!?

Ukyou: What's that supposed to mean? Listen up and well! I'm a hundred percent woman!!!"

"Saionji: You're a girl?
 * Exemplified and subverted again by the character Herb. When the tall, dark, powerful stranger who handily defeats is shown to be a woman, the cast reacts with surprise and shock. However, the subversion comes as it turns out that Herb is the Prince of the Musk Dynasty, who, having fallen into the same cursed spring as Ranma, also turns into a woman.
 * This is then inverted by Konatsu and Tsubasa, Ukyou's would-be suitors who everyone (including the audience) believed to be girls, right up until the very final page of their introductory story arcs --when their outfits are destroyed, one way or another. To be fair to Ukyou, she did know Tsubasa's true gender... she just didn't bother telling anyone.
 * In Bleach, (read only if you've seen Episode 41 or read Chapter 116) is a more long and drawn out version of this;, everyone assumes she's a man. In the manga, this was just an assumption on the part of the reader. The anime is more deceptive; . It doesn't help that she has the speech patterns of an old man.
 * In the anime Bastard!!! Arshes Nei was shown at first as a figure in full plate and rather bulky armor, which made impossible to tell that the character within that armor was, in fact, a slender female.
 * from Yu Yu Hakusho. She even disguises her voice and covers her face when she is first introduced.
 * One episode of Excel Saga concerns a mysterious masked man with a masculine voice. He and Nabeshin have a lot of Ho Yay, which Excel comments on - and then the mask is removed, showing a beautiful blond woman. Still with a masculine voice.
 * A bit of a drawn-out occurrence appears in Katekyo Hitman Reborn!. It is pretty much impossible to tell I-pin's gender, since she is a baby... Then she gets hit with the 10-year Bazooka. No romance (again, baby) but she does spend a lot of time with Lambo.
 * You think them being babies/kids has stopped the Lambo X I-Pin shippers?
 * Haruka in Sailor Moon, although there's no romance arc beyond her flirting with Usagi for the fun of it; she's already taken... by a woman, which helped hide her gender. Though due the fact that she appeared in the anime in her Senshi form before the reveal at the end of the episode introducing her, viewers are not as shocked as the characters. (It should be noted that before this episode, Uranus and Neptune DID show up in senshi form, but all the viewer was shown was a silhouette and the credits only listed them as "Mysterious Senshi 1 and 2"
 * Also, for the first few Uranus and Neptune appearances in the original manga, they were perceived not as two mysterious senshi, but as a mysterious senshi/Tuxedo Mask pair; and Haruka's flirting with Usagi was much heavier. It wasn't until after they joined with the other senshi that Uranus was perceived as a woman rather than a man.
 * Lan Fan in the Fullmetal Alchemist manga. When Ed uses alchemy to destroy her mask in their fight, he's so shocked to see she's a girl that she's able to both destroy his automail arm and drop a bomb before he can react.
 * Subverted the subtrope by not becoming Ed's love interest at all. In fact, she already has her own (there was a brief, mostly-played-for-laughs Ship Tease between Lan Fan's love interest and Ed's, though).
 * Also Major General Olivie Mira Armstrong, when Alex first mentions her, she could have been a male as well.
 * Kidd Summers at the start of the Pokémon movie: "Lucario and the Mystery of Mew", literally in armor. Semi-justified by the fact that everyone at the festival is in quasi-medieval costume.
 * in the manga Pokémon Special. Funnily enough, only Blue and Blaine knew until near the end of the Gold/Silver/Crystal arcs, then everyone finds out after.
 * Green found out while training her. The only ones shocked by that spoiler were Red, Crys, and later Gold.
 * Anabel and Angie in the main anime. Incidentally, they both end up developing a crush on Ash.
 * Zoroark turns out to be female in the movie.
 * Due to the voice acting in the dub, German viewers often thought Digimon Tamers's Renamon was supposed to be "male" (or at least gender-neutral -- it's a somewhat deliberately enigmatic digital lifeform in what's arguably a kids' show, after all). Which makes the final form a bit of a surprise.
 * Parodied in Steel Fist Riku. Chikara Toudou arrives to challenge Riku's father, but since he's not around, he decides to challenge the "son", Riku, instead. At this point, Riku has her chest bound flat, so it's understandable. But then, Riku tells him she's a girl, and he accuses her of pretending to try and get out of the fight. Then, during the fight, he notices the bump under Riku's shirt... and thinks "he" is concealing a weapon there. He finally gets it after he grabs her breast.
 * Odd variation in the Mahou Sensei Negima manga: Earlier in the manga we met Paio Zi, a member of a group of bounty hunters pursuing Nodoka had a rather... "healthy" appreciation for breasts boobies that bordered on the obsessive. Most readers found this character quite disturbing... until a recent chapter mostly set in a bathhouse, where the hunters are encountered again under peaceful circumstances, and Paio is revealed to be a girl, who proceeds to Skinship Grope the hell out of pretty much everybody within reach (and she moves fast), to the amusement of the fans. This comes across as a bit of a Double Standard, but she's really a lot less threatening without her fighting costume, which is rather monstrous and effectively quadruples (at least!) her body mass. Compare her in costume (Commanding the tentacled worm) with her out of it (Furo, remember? so may not be Work Safe).
 * What Double Standard? Ku Fei didn't hold back when she kicked Paio in the face.
 * Mostly by the fans, who were creeped out by Paio Zi at first, but then laughed their heads off when the truth came out.
 * There is a difference between Skinship Grope and what seems like attempted rape.
 * Enigmatic Minion Masquerade of Bakugan is actually . She uses her Stat-O-Vision Sinister Shades Mask Power to transform.
 * Noi of Dorohedoro does this in the first volume. She's one of the numerous masked badasses of the show; taller, bulkier and probably stronger than the entire male cast.
 * Stir from King of Bandit Jing does this.
 * In ''Adolescence of Utena, Saionji cuts Utena's shirt in their duel, leading to the following exchange:
 * Stir from King of Bandit Jing does this.
 * In ''Adolescence of Utena, Saionji cuts Utena's shirt in their duel, leading to the following exchange:

Utena: I don't remember saying I was a boy!"


 * In the Dragon Warrior anime, Daisy saves Abel's hide a few times before he finds out she is a girl.
 * Fist of the North Star has this pulled off by the Last General of Nanto, who dresses like a fearsome warlord. Once the helmet comes off though, the General is revealed to be none other than
 * A baddass inversion was used in Rei's debut. You see a woman in a pink cloak being harassed by thugs. You think a badass martial artist'll jump in and save the day. Then you end up surprised when the "woman" in the pink cloak turns out to be said martial arts badass Rei in disguise, luring said thugs to him.
 * Raiko Minamori in New Getter Robo, who is revealed to be a woman only after Ryoma tackles her and ends up grabbing a handful.
 * In Getter Robo Armageddon At the beginning of the series the kid is daughter of Dr.Saotome initially using boy's clothing.
 * Reversed in Liar Game in the second round
 * Ouran High School Host Club: Haruhi, if you watch the first episode unspoiled, which is pretty much impossible nowadays.
 * Glass Fleet combined this with Viewer Gender Confusion due to the fact that had a  voice actor. The big reveal isn't until episode seven. Afterwards,  style of dress does not change (spoiler text as this is a major plot point of the series).
 * In Yu-Gi-Oh! 5D's, the helmeted D-Wheeler shown in the third intro sequence turns out to be a blond woman named Sherry.
 * Kino's Journey:
 * Strangely, it is Japan in which this is easy to guess due to seemingly Cross-Dressing Voices, the English dub gives the character a much more ambiguous voice.
 * Though it's not uncommon in anime for adolescent males to have distinctly effeminate voice.
 * Full Metal Panic: In the Second Raid, Mithril agent Wraith is revealed to be woman. She disguised herself was an overweight man complete with a voice changer.
 * With Hinagiku taking the role of Silver Red (a superhero of a Sentai parody), Hayate the Combat Butler is setting itself up for this one. The other characters even think Red is a guy, despite the significant lack of male form (not just Hina's Pettanko status).
 * In Kirby of the Stars, Princess Rona initially introduces herself as the MALE bodyguard Vee to the decoy princess because she wanted to get to know the people of Cappytown as a normal person. It's not until her helmet falls off later on that any real girlishness is revealed. She still manages to kick Dedede's ass at the end in a swordfight even after being revealed as the actual princess. Though in this case, the deception was intentional, not just that wearing that particular suit or whatever was the most logical thing to do for an action hero.
 * Busujima from Busou Renkin.
 * A 1987 anime version of The Three Musketeers does this to.
 * In Death Note, Misa Amane is revealed to the readers to be the second Kira soon after her activities become known to the other characters. In the English versions at least, Light and the investigators continue to refer to The Second Kira by the male pronoun (probably for the sake of convenience, as they use "he" when referring to the first Kira too) until they learn more about her.
 * Played with in Space Pirate Mito. During a fight, Big Bad Ranban's helmet is knocked off, revealing not only a female face underneath, but the same face as Aoi's mother, the titular Mito. Ranban reveals that it's just a mail suit, which Mito also wears, modeled on the first queen of the galaxy. Later on, however,.
 * In One Piece movie 4. the little kid whom Luffy and Co. encountered was revealed to be a girl dressed in boy's clothing near the end.
 * from Angel Sanctuary. The promising scientist 's success elicited jealousy from her male peers, who raped her. Branded a Fallen Angel for becoming "tainted", she sold herself in desperation to Sandalphon, who whitened her hair and altered her face and body type. Since the true  died years ago in combat, she took his name  to hide her identity after she ascended into the Seraph rank.
 * Used during the Naruto Land of Birds filler arc. An armored, flying specter wielding a naginata appeared to haunt a daimyo's castle which had recently seen great misfortune; the specter seemed intent on uncovering if an assassin had slain the former daimyo and his daughter. It was eventually revealed that the specter was.
 * Subverted much earlier during the Land of Waves of arc. Haku's first appearance showed her to be highly-skilled and convinced even Kakashi that she was a threat while wearing bulky robes that could disguise a feminine form. A chance meeting with Naruto while in civvies set up the possibility of a forbidden romance... and then Haku Dropped a Bridget On Him.
 * In Durarara, Celty's gender isn't clear when she first appears thanks to camera angles and lighting, although her feminine form is much more apparent later on.
 * It's apparently less obvious in-universe than it is to the viewers; neither Shizuo nor Tom knew that Celty was female until Shinra told them.
 * from Toriko starts off appearing to be a very bishie man.
 * Ice Revolution: Most of Masaka's friends at the skating rink thought she was a boy... until she took the ice for her first performance. Heck, her own coach didn't even notice she was a girl until she told him.
 * The red man in Deadman Wonderland. Ganta is so screwed when he found out the nemesis he hated so much turns out to be
 * Kei in Iria Zeiram the Animation. She's pre-adolescent, so there's no way to distinguish that she's a girl dressed in boy's clothes until late in the series when Fujikuro literally sniffed out her gender.
 * In episode 12 of Blue Exorcist,
 * The titular character in Osamu Tezuka's . It doesn't help that she was told she was boy by her parents.
 * In Sgt Frog, many characters first think that Private Tamama is a female due to his cute appearance and voice. Later on in the series, Tamama himself, along with most of the rest of the cast, falls victim to this trope when a Keronian named Karara comes to Earth to see the ARMPIT Platoon. It's not made apparent that she's female until she leaves a goodbye note when she leaves at the end of the episode, saying that Tamama left such a huge impression on her that she wants to marry him when she grows up. In all the character's defense, an actual female Keronian hadn't shown up before then.
 * Brilliantly pulled in Infinite Stratos. Ichika accomplishes the impossible and moves an IS, something that's said to be impossible to be done by males. He gets himself enrolled in an all-girl school... then after a while, another male by the name of Charles Dunoa is transferred into the class and said to have accomplished the same feat. Dunoa is awfully shy around Ichika in the locker room and Yup, Dunoa is definitely not a guy. "He" later explains that  A few days later, Ichika's class receives another transfer student. Everyone, say hello to Charlotte Dunoa. Naturally, everyone in the class knows Charlotte and Ichika used the bathhouse together the previous night and instantly make the assumption he must've known and took advantage of it. Cue Rin bursting into the classroom with her IS and firing a full-powered shot at Ichika's head.
 * And as a little extra, Charles/Charlotte also happens to be a Char Clone and later becomes a Love Interest for Ichika.
 * And as a litlle extra extra, her nickname, given to her by Ichika, IS Char. Go figure.
 * Fushigi Yuugi has Soi, who was a person wearing a cloak for a few chapters before revealing herself as a woman.
 * A villainous example appeared in Brain Powerd - the enigmatic Baron who begins to appear late in the show is quite fearsome, helping the villain Jonathan transform his Grand Cher into a borderline Eldritch Abomination known as the 'Baronz'. His reasons seem mysterious and Chessmaster-y, but...
 * Inverted in Baccano, where Claire Stanfield, the expert assassin named Luck had hired, turns out not to be the fatigues-wearing Action Survivor woman that'd been making her way across the train, but rather

Comic Books
"My name is Tristan. Sir Tristan."
 * One of the regular supporting heroes in Paul Grist's Jack Staff is Tom Tom the Robot Man, a towering, super-strong robot with the power of flight. It's a genuinely bizarre and unexpected moment when it's discovered that "he" is effectively a suit of powered armour being piloted by a disabled girl genius to fight crime.
 * In the one-shot crossover "Spider-Man vs. Wolverine", both heroes are on the trail of Wolverine's former partner, named "Charlie", which is given as being short for: "Charlemagne". When Wolverine finally catches up with Charlie, the rogue agent is revealed to be a "she". Wolverine naturally knew all along, but Spidey, as well as the READER were kept in the dark by clever avoidance of gender-specific pronouns (not to mention a flashback where "Charlie" is deliberately shown in gender-neutral disguise). It's implied that Charlemagne uses the ambiguous nature of her name as an additional cover to her identity.
 * In X-Men, Professor X's primary love interest Lilandra was introduced in a running subplot in which he was having ominous visions of space battles and a menacing armored figure. When the figure finally showed up and took off its helmet, it wasn't quite what he was expecting.
 * The original Ronin in New Avengers turned out to be Daredevil's love interest Echo (after a minor Red Herring that it was DD himself).
 * Julie-Su from the Sonic the Hedgehog comic.
 * of Empowered is a dramatic example, as eventually revealed to Emp; and  are ex-lovers, whose first meeting (without a Samus Is a Girl scene) was shown in flashback the following volume.
 * in Secret Six, turns out to be his.
 * Sasquatch from Alpha Flight is usually male in the main continuity, but in the Ultimate Universe, when the team returns to base after fighting the X-Men, Sasquatch resumes human form and turns out to be the very female Rahne Sinclair, who in the main Marvel Universe is the werewolf Wolfsbane. There were some hints to this beforehand though; readers may have wondered why "he" had ribbons in "his" hair in Sasquatch form.
 * Sasquatch from The Exiles as well. First going into human form: "What surprises you more, that I'm a woman or that I'm black?"
 * Shining Knight, from Grant Morrison's Seven Soldiers of Victory, is revealed to be a girl at the end of her portion of the series.
 * Colonel Randall in Dark Horse's early Terminator comics is introduced as a gritty soldier in combat fatigues and a face-obscuring helmet, and only referred to as 'the Colonel'. This is really only to build up to the money shot, where, after having stripped down to go through Skynet's time machine, Colonel Mary Randall blows away a terminator and is shown to be... a hot nekkid babe! Needless to say, on arriving in the 20th century she starts wearing tight minidresses.
 * In The Sandman, Death's name is mentioned well before we see her. Gaiman intended for most readers to assume Death of the Endless would be male and menacing ... until we saw her.
 * In-character example from the same series:
 * The Surrogates features a setting where normal people no longer interact with each other in person, but instead use a humanoid robot as a proxy. As a result, cross-gender surrogates are common. One of the first surrogates we see is a cross-gender surrogate, and the male Corrupt Corporate Executive is revealed to actually be a woman. Both of them masqueraded as a person of the opposite gender to get ahead in their respective fields.
 * In Camelot 3000, Merlin sends Tom to a wedding to awaken the memories of a reincarnated Round Table knight. The homing-amulet he's carrying leads him to the couple at the altar. Tom assumes it's the groom he's looking for, but it's actually the bride whom Sir Tristan has been reborn as.
 * Of course, the now awoken Tristan fully identifies as a man and draws a great deal of angst from it.


 * Taz in the Atari Force second series was referred to as being male up until Morphea discovered.
 * In Scud the Disposable Assassin, Sussudio is introduced this way.

Film - Animated
"Hear that, Jane? She thinks you're a man.
 * Kevin in Up. Russell initially thought Kevin was a male, but later revealed to be a female when she calls to her chicks. He still refers to Kevin as a he.
 * From Final Fantasy the Spirits Within, before the soldiers take off their helmets:

I think she's an idiot."


 * Heavy Metal: The title character of the last story, Taarna, is summoned by the city's elders to fight the horde of evil invaders. The elders don't use any gender-specific words when speaking of the last of the Taarakians whom they're summoning, and when Taarna does arrive, she flies into the city on a pterodactyl-like steed wearing a hooded robe. Only when she lands in the city and dismounts her steed does Taarna reveal her gender by removing her hood (and shortly thereafter, everything else to keep up the film's quota).
 * Technically, the stitchpunks of 9|Nine are asexual constructs. This trope is still invoked with 7, whose female voice isn't heard until after "she" has demonstrated "her" combat prowess.
 * The Dragon turns out to be this in the original Shrek.
 * Kitty, in Puss in Boots.
 * In Batman: Mask of the Phantasm,.

Film - Live-Action
"Tony: Good God, you're a woman!"
 * Demetra, from Spy Kids 3D: Game Over, wore a head-obscuring helmet during her stay with the gang that Juni joins. (While there was slightly bulky armor, I don't think it would've mattered much on that front, her being a preteen at the time.) Romance Arc? Check.
 * Maid Marian's initial appearance in Robin Hood: Prince of Thieves, followed shortly after by Chickification.
 * From Sky High, power-armoured supervillain Royal Pain turned out to be
 * In Return of the Jedi:
 * Boushh is.
 * Rumored to have been the case for Boba Fett for a while, which would have put quite a different spin on the scene at Jabba's palace, where Boba makes a pass at one of the dancer girls. It's hinted at in a young reader book, and in fact his appearance in that book was later retconned to have been his daughter impersonating him.
 * This seemed to be the idea behind Nyssa's first scene in Blade 2. It didn't quite work. In fact, it would probably count as a genuinely surprising subversion of this trope if an armored antagonist were to wordlessly, facelessly appear, go toe-to-toe with the male protagonist using acrobatic moves, and then be revealed to not be female.
 * Knightriders, Sir Rocky.
 * Thunderball. A motorcyclist kills a man driving a car (who's chasing James Bond) and rides away. After running the cycle into a ditch, the cyclist takes off the helmet and reveals that she's SPECTRE assassin Fiona Volpe.
 * In Dragonslayer (1981) a character turns out to be
 * Hackers: Neither Dade nor the audience know that Dade's rival, Acid Burn, is actually his love interest, Kate Libby, until a hacker lets that information slip about halfway through the film. Dade's fellow hackers do know who Acid Burn is, but when Dade initially assumes Acid Burn is male--"Do you know who he is?"--they gladly let him go right on thinking that--"No, I don't know who he is".
 * From Lord Nikon's point of view, this is the case with Zero Cool, Dade's hacker alias when he was a kid (and responsible for one of the worst cyber-attacks in history). Being black, Nikon naturally assumed so was Dade.
 * Barbarella in the beginning of the original film, where a bulky spacesuit is removed, and Fan Service ensues.
 * Trinity in The Matrix, from Neo's point of view; he'd heard of Trinity in Cyberspace but assumed it to be a guy. Trinity replies that "most guys do."
 * Terminator Salvation: a jet pilot, who takes down a flying robot, and who ejects after an engine is shot by the machines which later causes an explosion, is only called "Williams". Marcus goes saving Williams, who is hanging from a telephone tower. Pilot takes helmet off, turns out to be a woman, Blair Williams.
 * Racecar driver A.J. Ferguson in the feature film version of The Little Rascals turns out in the end to be..., shocking all the young male members of The He-Man-Woman-Haters club.
 * In The Son Of Robin Hood Little John has a problem with Robin's heir. Three guesses to what it is.
 * The Sting has one
 * A shocking variant was used in Hellbound Hellraiser II, in which the gruesome Cenobites are involuntarily transformed back to their original human guises by the Lament Configuration. One Cenobite whose facial features had been burned away, leaving nothing but scar tissue and chattering teeth, is revealed to be.
 * Subverted in What's Up, Tiger Lily?, a Japanese spy movie with new dialog by Woody Allen. An escaped prisoner in a head-covering scarf hops into the hero's car and drives off, then pulls off the headgear, revealing herself as a sexy girl. The hero reacts in surprise: "(whistle)... an Oriental!"
 * In Pitch Black,
 * Pocket Ninjas when the White Dragon at the fight scene near the end was revealed to be Tanya.
 * Subverted in Aliens. Male Marine to Action Girl Vasquez, as Vasquez does pullups in the locker room: "Hey Vasquez, you ever been mistaken for a man?" Vasquez: "No. Have you?"
 * In the film The Last Legion, familiarity with those trope allows one to quickly surmise that Why else would she wear a helm with an aventail like that?
 * The opening scene of Iron Man has Tony exclaim in suprise when he realizes that one of his three (military) escorts is actually female. She's revealed by her feminine voice the first time she speaks up.


 * Quorra's introduction in Tron: Legacy has elements of this, as she wears a motorcycle helmet the whole time and even uses a voice modulator. Averted in that it's pretty clear from her outfit that she's a woman, and that the helmet and modulator are intended to hide her identity rather than her gender.
 * In Indiana Jones and the Last Crusade, Indy and Marcus Brody are a bit surprised to see their contact is, in fact, Dr. Elsa Schneider.
 * in Dick Tracy. The Reveal is actually quite a Tear Jerker.
 * In Slasher Films featuring female killers, the villain's gender is usually hidden by either a disguise, camera angles, Murderer POV, or some combination of the three. Plus, they're probably played by random stuntpeople up until The Reveal.
 * In Stick It, the hero in the introduction is apparently a cool dude who rides BMX and does crazy tricks. It's only after "he" starts running from the police that "he" sheds his big hoodie to reveal Haley, the female protagonist.
 * In Sky Captain and The World of Tomorrow, Polly reacts poorly when she meets Sky Captain's old mate, a carrier captain named Franky. In turns out that Franky's birth name is Francesca. And that Franky is Angelina Jolie wearing a kickass uniform and an Eyepatch of Power.
 * In the Vincent Price film Theatre of Blood Lionheart's lead henchman the British accented guy with the hippie glases, afro, and beard turns out to be his daughter Edwina (Dianna Rigg).
 * In I Am Legend Will Smith refers to his dog as "Sam", until just before he has to put it down, when he addresses it as "Samantha". The movie treats this entirely meaningless un-plot-point as a major case of this trope.
 * Or maybe it doesn't...
 * In Your Highness, the heroes meet a mighty warrior in the arena, and are surprised when she removes her cloak.

Literature

 * Britomart in The Faerie Queene has three distinct "Bobs": The reader learns she is a woman after she defeats Guyon, but the first character to learn she is a woman is the Redcrosse Knight, after she saves him from a gang of six other knights. Her love interest is Artegall -- Love At First Sight for her, Love At First Punch for him.
 * Bradamante in Orlando Furioso, of whom Britomart is an Expy, does this as well in the... unusual tale of her and Princess Fiordispina.
 * In one of the cleverest examples of this trope, Joanne Harris' Gentlemen and Players has the . This is revealed close to the end of the book.
 * in Robert A. Heinlein's Tunnel In The Sky.
 * Aravis in The Horse and his Boy -- Shasta/ is her "Bob".
 * This happens in one of the Flashman novels, where he and a rebel against the Russian empire are rescued from prison by a group which includes a woman whose face is veiled. He is at first offput when she kisses him, knowing the cultural tradition of male bonding among warriors, but then relaxes when he notices her female attributes.
 * Sir George, the knight who saves Princess Andromeda from a dragon in one of Mercedes Lackey's Tales of the Five Hundred Kingdoms, is actually Georgina.
 * Andre de la Croix in the Time Wars series. Also a Sweet Polly Oliver, but the reader doesn't find out until after she's kicked serious butt at a tournament.
 * In Esther Friesner's Majyk trilogy, at one point the hero is rescued by a masked swashbuckler who identifies himself only as "a blade for justice." This eventually turns out to be . Even after The Reveal, she keeps up the masquerade, finding swashbuckling to be a rewarding career.
 * Eowyn from The Lord of the Rings. She does appear previously in the story, but when she disguises herself as a man she's introduced and referred to as a new male character, until she reveals herself. A Genre Savvy reader will likely have already identified her by that point, though.
 * In the book, anyway. In the movie she never introduces herself as the male character and nobody's fooled by the disguise; the director's commentary has Peter Jackson stating that they deviated from the book in that regard because they had to - it was simply impossible to make it convincing and they didn't want to insult the viewers' intelligence with a Paper-Thin Disguise.
 * In A Song of Ice and Fire, Catelyn watches Brienne of Tarth win a tournament and assumes she's a man because she's encased in plate armor. Because Brienne is hulking, ugly, flat-chested, and often wears warrior garb, she admits to being frequently taken for a man.
 * Terry Pratchett's Sourcery,
 * Although in this case, it's less a matter of bulky clothes, the book simply avoids gender specific pronouns at the start.
 * Also Monstrous Regiment.  in the regiment is revealed to be a girl/woman.
 * Lest we forget, the  in Guards, Guards is one, too.
 * In Feet of Clay, it's revealed that  is a female dwarf to the reader fairly quickly. As a lampoon on Our Dwarves Are All the Same, Dwarven culture is so male-centric that females typically behave and masquerade as men stated that all dwarves are considered dwarves without distinction of sex. This can cause confusion when two dwarves like each other and need to delicately find out if they have met a friend or a mate. Angua detects her secret and coaches her to slowly adopt feminine behavior, which causes a lot of confusion among her other co-workers. She ultimately comes out of the closet and   She also starts wearing dresses. Chainmail ones with an axe... she said she was female, she never said she wasn't a dwarf.
 * Subverted earlier in the series as well. When Angua is introduced in Men At Arms (But she's a w...), it is obvious right away that she is female, but it's not until later that the reader finds out that she is a werewolf, and some of the characters don't find out until the end.
 * Tamora Pierce plays with this trope a bit. The readers know very well that Alanna/Kel is a girl (especially Alanna); it's the various characters who get the shock.
 * Matt Ruff's Set This House in Order when we find out.
 * P. Berling's "Die Ketzerin" ("The Heretic") begins with a knight tournament, and the winner is a woman, namely the main heroine.
 * in The City Who Fought.
 * in Grace Chetwin's YA series, Gom Gobblechuck.
 * Erast Fandorin's is revealed to be a girl in the final showdown, who kept her tightly-knit gang together with The Power of Love.
 * In the Conan story Conan is forced to leave a battle because of additional forces coming in for their own reasons. While trying to work out how to extract the girl who was hiding in a building the far side of the battlefield, one of his soldiers tells him it's taken care of and takes off "his" helmet.
 * Crackers, George and Harold's pet pterodactyl in some of the Captain Underpants books, likely falls into this. After being hypnotised (along with Sulu the bionic hamster) into being evil, Crackers in fact does good. It was previously established that the doohickey that does the hypnotising causes females to do the opposite of whatever they are commanded to do. Plus, all of the pronouns relating to Crackers are highlighted-a fact which George and Harold notice.
 * Harry Potter: Norbert the Norwegian Ridgeback is revealed to be female by the series' end. In light of this, her name was changed to Norberta.
 * Director Inoue Sato in Dan Brown's The Lost Symbol. No awesome armor, but a surgically raspy voice and a cell phone connection do the trick.
 * in The Edge Chronicles.
 * From Russia with Love: Ian Fleming goes into detail describing the hideous appearance of Dirty Communist Rosa Klebb, before ending with the words "She pulled up her skirt and sat down".
 * Kitai from the Codex Alera gets this twice. From the same person. You'd think that what with Tavi being as smart as he is he'd pick up on things like that.
 * In Robert J. Sawyer's Calculating God,
 * In one of Akutagawa's short stories, "The Martyr", the young man who was adopted by the Catholic church had been assigned the name "Lorenzo". Later, "he" was excommunicated from the Catholic church because a girl accused "him" of fathering her child. After "he" had saved her child from a burning house and the mother revealed the truth about the child's paternity, Lorenzo was revealed to be a woman all along.
 * Wasn't this based on a true story? I'm sure there was a saint who was raised a monk, kicked out for 'fathering a child', but never admitted she was female - they only found out when they went to bury her. I'm off to google to find out who this was...
 * Saint Marina the Monk
 * Lampshaded straightforwardly in John Nichol's novel Point of Impact, in which Jane, a female member of aircrew, is advised, after stepping down from an aircraft, to remove her helmet and shake out a mane of blonde hair - and she does. Nichol is an ex Tornado navigator famous for failing to set up an aircraft correctly on the final run into an Iraqi airbase in January 1991; understandable mistake, but not really the time to make it since the blunder earned him and his pilot a multi-week stay at the pleasure of the Iraqi regime and their baseball bats. Ironically, Nichol probably left the RAF around the time female fast-jet aircrew began to appear.
 * In Patricia Briggs' When Demons Walk, Sham is often mistaken for a pubescent boy, a resemblance she augments with masculine dress and hair. Kerim has an entire conversation with "him", Talbot watches "his" interrogation, and when Kerim is attacked Sham throws the knife that kills the attacker. When they try to find him again, they can't figure out how he managed to disappear so completely, until an amused informant finally reveals that they should start asking about local women.
 * At a Worldcon panel, an anecdote about an accidental, out-of-story example from The Hunger Games was discussed: The author, Suzanne Collins, works as a teacher, and at one point a boy in her class, who was most of the way through the first book, gushed about Katniss to her, saying "He's so cool!". Collins pointed out that Katniss was a girl, to which the boy responded, "Girls don't hunt!"
 * This is the Twist Ending of The Turbulent Term of Tyke Tiler by Gene Kemp.
 * In Star Wars: The Old Republic: Fatal Alliance, Dao Stryver is a tall, tough Mandalorian wearing full body armor and helmet. The novel consistently refers to Stryver as "he." He has a deep, male voice, filtered through his armor. At the end, Stryver turns out to be a Gektl female, although one character knew it all along. Since most Mandalorians shown in films and games tend to be male humans, this was a big shock. This is even more jarring in the audiobook, where the narrator makes an effort to make Stryver to sound like a tough guy, using special effects to add to the feel of the character. Then comes the Gektl female with Sssssnaketalk.
 * In the Ciaphas Cain novel Duty Calls, Cain is saved by a warrior in Powered Armour who turns out to be Amberley Vail. It's not her first appearance, but the unidentified warrior is separately established under that description before the reveal.
 * In Iain M Banks' The Wasp Factory,
 * In the first in the A to Z Mysteries series ("The Absent Author"), our detectives try to get reclusive mystery author Wallis Wallace to show up. Wallis doesn't show up, but the gang finds him kidnapped...
 * Jirel of Joiry is revealed this way in her first story "Black God's Kiss".
 * In James Herbert's Nobody True, the ghost protagonist spends a lot of time stalking a hideously deformed serial killer with psychic powers named Alex, and even ends up possessing the killer's dead body to use it to save his family...only to find that Alex was short for Alexandra, and she was too deformed to notice her breasts. Alex even walked like a man.
 * In Firebird, Brennen Caldwell initially assumes Firebird Angelo is a man, simply because she was a pilot in the attack phalanx of the Netaian invasion force. His assumption is corrected after she is captured.
 * In Icerigger, it's not revealed that  is female until well after the Horde has been driven from Sofold.
 * Boba Fett's estranged daughter Ailyn Vel impersonated her father for a period of time. So deadly and ruthless was she that everyone who met her during this period thought she really was her father--but her utter lack of ethics went beyond even Fett's harsh methods, and years later the truth was eventually discovered.
 * In the Black Company novels, Soulcatcher, one of the Ten Who Were Taken is an interesting example. It's well known that three of the Taken are female, but owing to the Taken's habits of concealing their true features, no one's quite sure which and just call them all "he" indescriminately. Soulcatcher herself further confuses matters by the fact that her voice changes continually to reflect the souls she's stolen, so her voice is sometimes male, sometimes female. However, it is noted that Catcher's masculine clothing doesn't fully conceal her shape and "he" has fairly effeminte mannerisms- at the end of the first book, Catcher's ubiquitous helmet comes off and she's revealed to actually be a woman. Later in the series she makes no attempt to disguise her gender, even when hiding her face.

Live Action TV
"Titus:(smiling confusedly) Ch-Charlie. That's one of those trick names. So that means...
 * Vala in Stargate SG-1. Downright hilarious when she starts trying to seduce Daniel while wearing the armor of an artificially engineered monster super-soldier, and with her voice masked to match... A bit of a variation in that Vala was the one who attacked the ship and captured Daniel.
 * Also, in the pilot episode of Stargate SG-1 General Hammond mentions that he has assigned Captain Sam Carter, their top Stargate expert, to Colonel O'Neill's team. Col. O'Neill asks where he is transferring from. From the door, Captain Carter tells him that she is transferring from the Pentagon.
 * Similarly Aeryn Sun of Farscape (also played by Claudia Black, incidentally) is first seen as a fearsome person in a bulky, black, armored spacesuit with a smoked-glass helmet, on a spaceship full of bizarre alien creatures. Off comes the helmet...and you see a fearsome, angry (but attractive) woman in an armored spacesuit.
 * While no helmet or concealment is involved, in the episode "The Flax" one very masculine-looking Zenetan pirate (played by a male actor) is revealed to be female of her species by the end of one Farscape episode. In their race, both genders look androgynous, and a female can pass as male.
 * In Kamen Rider Faiz, Kamen Rider Delta was revealed to be a woman encountered by the cast previously (until then, we'd also never seen Delta in real action; just baddies getting wasted and Delta standing there). In an example even worse than the Zelda one, she's just about to suit up for the first time since we found out who she was and have her first onscreen fight scene... when she's impaled by a villain and her armor taken and used by another. (The Kamen Rider franchise, either because of tradition or extreme and utterly shameless sexism -- hopefully, the former -- has had exclusively male heroes since it began in the 1970s, with the rare exceptions eventually being executed by the plot for their audacity. Nobody savvy about the franchise expected her to survive long, though getting to see her in action once would've been nice.)
 * Well they did have another female transform into Delta. For about five seconds... then she gets hit once and de-transforms. Japan just changes very slowly,simple as that.
 * Ironically (and probably even more sexist), the Riders who we know are women from day 1, or who are evil, don't last long either, but they do last longer than any and all cases of Samus Is a Girl.
 * In Kamen Rider Fourze,
 * No mortal peril involved (and probably no relationship, but this is MacGyver we're talking about), but a female T-38 pilot does this on an episode of MacGyver after she gives Mac a free flight. Get your minds out of the gutter...
 * The opening of the Witchblade TV show had a figure going about his day - putting on his boxer shorts, putting on his leather jacket, and getting on his motorbike, before 'he' takes off his motorcycle helmet and it's a woman.
 * Doesn't help that there's such thing as women's boxers.
 * In TNA Wrestling, the Latin American Xchange was often helped in their matches against the Rock 'n Rave Infection by a mysterious latino in baggy gangsta attire with a bandana covering "his" face. Said mystery "man" often attacked the Infection's valet, Christy Hemme, prompting her to repeatedly complain to on-air authority figure Jim Cornette about the "man-on-woman violence" going on. Of course, the mystery member of LAX later revealed herself as a latina named Salinas, thus making the Rock 'n Rave Infection look like a bunch of whiners. And immediately after The Reveal, her attire went from concealing to Stripperiffic. Hey, it is Professional Wrestling after all.
 * The 2006 series of Robin Hood tries to pull this off with the identity of the Night Watchman, but doesn't quite manage it.
 * It also does something similar with Djaq- the first confirmation the astute audience get of her gender is Will walking in on her naked (ritual cleansing pre-prayer in fact).
 * In one episode of Chris Titus', um, Titus, his girlfriend's niece and ward Amy is distraught over her breakup with "Charlie." After an episode-long flashback to the title character's high school days, Titus' girlfriend shows "Charlie" in. It's a girl.

Amy: -I'm a big fat dyke? Yeah."

"Lewis: Which one of you is Stivers, I'mma slap you.
 * Power Rangers SPD: . Double points for . This actually caused a bit of a stir on the Rangerboard forum: one member, being an expert in digital voice manipulation, Crowning Moment of Awesome?
 * They tried pulling this off again in RPM with Dr. K (key word being tried), but it failed for two big reasons: One, the voice distortion she used still sounded too feminine, and two, a trailer that got leaked showed a girl with the label Dr. K. And even then, this isn't getting a spoiler tag due to the fact that the reveal happened in episode 4!
 * It's also done in Power Rangers Ninja Storm, in the second part of the episode "The Samurai's Journey", with Cam's mother Miko.
 * Kyle XY:.
 * From the Bones episode "Fire in the Ice", Albie the poker ring organizer. Booth is very shocked. Perhaps because he recognizes her from his Buffy days?
 * Subverted in the first episode of Get Smart. We can tell Agent 99 is a girl, it just takes Max a while to realize it.
 * A funnier one occurs in a later episode where Max agrees to host a scientist who has the power of invisibility at his house while 99 (now married to him) is on vacation. He then finds out after the scientist becomes visible that the scientist is female (and even the Chief didn't know!). Now he must deal with hosting a female while his wife is out (think about how that would look to others). It gets worse when 99 comes back from her trip early and accuses him of cheating when she finds him; thankfully they sort it out.
 * A textbook example, from a second season episode of Merlin, we see.
 * In fairness, there was a pretty good hint -
 * Doctor Who:
 * "Remembrance of the Daleks": Made more effective by having a voice of the opposite gender before The Reveal.
 * "The Impossible Astronaut":
 * "The Daleks' Master Plan": Mavic Chen and his aide decide to call out their toughest Space Security Agent to apprehend the Doctor and company. It takes several scenes before we establish that "Kingdom"'s full name is "Sara Kingdom."
 * In the less than impressive sequel to the Sam Neil version of Merlin, Merlin's Apprentice Squire Brian turns out to be Squire Brianna.
 * Blackadder: "I always thought that Jamie and Angus were such fine boys." "Angus is a girl."
 * The Blackadder the Third episode "Amy and Amiability" has a subplot involving a mysterious highwayman called "The Shadow". It turns out to be Amy Hardwood, a woman he had earlier tried to fix the Prince Regent up with.
 * Homicide: Life On the Street: Lewis' first reaction to Det. Teri Stivers in Season 5 is reminiscent of this.

Stivers: I'd like to see you try, pal!"


 * In the pilot episode of Las Vegas, Danny looked all over town trying to find the mysterious casino host, Sam. He only found out Sam was female after she'd already pumped him for information, posing as her own secretary.
 * In the fourth season of Solitary, Number 3 was in their early twenties, and an ex-high school football player. And she was a girl. While the viewer knew from the start she was female, all the other numbers thought she was a boy. Number 3 eventually made it to the final three (and eventually won), which is when the other two finalist (2 and 6) found out she was a girl. They were a bit surprised.
 * Season 2 of Warehouse 13 features.
 * In Psych,  is revealed to be  . The surprise of the Reveal is slightly more justified than most cases of this trope, in the defense of the main characters, what with her
 * In the first scene of the pilot of Lois and Clark a young man with a mustache and beard enters the Daily Planet. He sits down at a desk, then removes the disguise to reveal that he is actually Lois Lane, who was working on an undercover story. Lois also cross-dresses in a season 2 episode, where neither her boss nor Clark recognize her immediately.
 * Ziggy Vadas from Life.
 * Community: Greendale's Human Being mascot is revealed to be portrayed by a female student during a webisode.
 * In Castle, is revealed to be a previously unsuspected woman.
 * In the first Hercules: The Legendary Journeys episode/pilot movie, much suspense is made of the nature of the "beasts" and the eventual dramatic reveal that they are, in fact, women. This would be much more dramatic if the episode weren't called Hercules and the Amazon Women.

Manhwa

 * Witch Hunter pulls this card with  who is initially thought to be genderless due to   and all that, but when   breaks  first seal, it's true form is revealed to be this. Tasha is, naturally, shocked.

Music

 * The music video for Prodigy's "Smack My Bitch Up". The reveal is at the end when the camera (from a first-person perspective) looks at a mirror. Before this she went to a bar, got drunk, beat up patrons and groped hot girls before returning home and passing out in front of a mirror.
 * A similar "woman doing manly things only revealed to be a woman at the end" music video is Bush's "Machinehead".
 * Turkey actually used this in their performance in the Eurovision Song Contest 2010, "We Could Be the Same" by maNga. Watch it here.
 * They must not have been trying that hard, because one good look at the figure makes it really obvious what her gender is.
 * The trance artist formerly known as Hybrid Factor was originally pictured as Steve Bailey, but later revealed to be Aimee, his sister. She now goes bt the artist name Aimee B.
 * Many promotional videos of the British Invasion band The Honeycombs attempted to hide the fact that their drummer, Honey Lantree, was female until some point later in the film clip (most notable is their performance of "Have I The Right?" in the 1965 concert film Pop Gear. They then do the same damn thing the next time they appear in the film, performing "Eyes")

Newspaper Comics

 * In Funky Winkerbean, The Eliminator was a Enfante Terrible arcade gamer of such skill, he could make a Defender machine tilt like a pinball game. His face was always covered by a visored helmet (a Shout-Out to Darth Vader, as The Empire Strikes Back was THE hot movie at the time of his debut). Midway through the first Time Skip, the grown-up Eliminator was reintroduced... as Donna, a hot blond woman. She eventually ended up dating and marrying Crazy Harry, who'd considered The Eliminator his nemesis back in high school.
 * In Mother Goose and Grimm, Grimm was shocked to learn that his hero, the star of the TV show Karl the Wonder Poodle, was a female poodle named Karla.

Tabletop Games

 * Ravenloft had a series of supplements called the Gazetteers, which featured a scholar known as S who traveled around the major domains of the setting and chronicled their cultures. Everyone assumed S was a man until Gazetteer III, which featured a throwaway line about S's struggles to manage the layers of corsets, skirts, and petticoats that one domain expected its citizens to wear. Even then, some fans continued to insist that S was a man (apparently more willing to believe the character to be a drag queen than a woman), and it wasn't until an actual illustration of her appeared in Gazetteer IV that the argument was put to rest.

Video Games

 * Obviously, Samus Aran herself from Metroid. Eventually subverted as, over the course of the series, developers have gone further and further out of their way to point out that she's a girl.
 * Zero Suit? Seriously, Other M? Did Adam not authorize clothes or something?
 * Also important to note that Samus was always female and that this wasn't a retcon; the original design team decided that she should be, because why not?
 * The localization team for the first game did, however, imply in the manual that Samus was male.
 * Ivysaur from Brawl was obviously female in the Japanese version, but apparently the English localization team didn't get the memo and gave her a masculine voice.
 * Speaking of Pokémon, many Pokémon like Machoke, Machamp, the Conkeldurr line, Kadabra, Alakazam and Emboar look manly, but have a 25% chance of being female (12.5% in Emboar's case).
 * Zelda's disguise as the male Sheik in The Legend of Zelda Ocarina of Time, who was designed with a male character model to keep the disguise more convincing. Programmers admitted she didn't get a more realistic design until Super Smash Bros. Brawl. Nevertheless, there's endless Fan Wank as to the nature of the disguise, especially since Zelda seems to have entirely different abilities, powers, and eyes than Sheik.
 * It states right on her trophy in Melee that she uses magic to change her clothing as well as her skin and eye color.
 * For some time, there was a very popular fan theory which stated that Sheik IS male, and that Zelda not only changes appearance but also gender when she transforms. Word of God has since stated that this is not so; Zelda can't change her entire body like that, just a few surface details.
 * Along with realistic design, Sheik became rather more obviously female in Brawl.
 * It's even more obvious in the beta version, too obvious thus they changed her. Sheik had a somewhat more feminine haircut, looked more round (and thus female), and had blue eyes.
 * And guess what? Sheik shows to be feminine, too (like she did in Brawl), in the 3DS remake. Too bad she still didn't unmask herself.
 * And, as of Skyward Sword, guess who/what else is female?
 * Syfa/Sypha from Castlevania III (only because a Blind Idiot Translation used the wrong pronouns).
 * One particular guide writer is very bad about accepting this fact, and insists that Sypha is male. Never mind the ending if you finish with Sypha, which involves Trevor and her getting married. Never mind that this marriage led to Juste Belmont of Castlevania: Harmony of Dissonance being able to use magic. Never mind how you can fight clones of Sypha (as well as Trevor and Grant) in Symphony of the Night and Portrait of Ruin, and Sypha's sprites show her in a revealing/flowing white robe with a very female voice.
 * It's pretty clear that for whatever reason, you're not supposed to know that she's a she until you complete the game with her (and the "mistranslation" was deliberate). Y'know like, oh... Samus Aran?
 * Not to mention that the gameplay does not really try to hide the fact that Sypha is a woman; aside from seeing a largely feminine figure when she opens her cloak to cast spells, and her head shot at the top of the screen, she also makes a distinctly female-sounding grunt whenever she takes a hit.
 * Just to make sure the audience knows Sypha is a woman, in Judgment she has quite nice breasts, and her breasts are even a joke in Maria Renard's story. In addition, her ending confirms that she was deliberately posing as a man in Castlevania III.
 * Here is the sprite for the playable Old Axe Armor from Castlevania: Portrait of Ruin. here is an official piece of artwork of the same character.
 * In Kid Icarus: Uprising, it turns out
 * This is the twist in Akira's ending in Rival Schools: United By Fate. The introduction of the story mode introduces her as the younger brother of gang leader Daigo Kazama and refers to her as male. The masquerade is carried on throughout the story, and even in her "bad" ending - only when you achieve the "good" ending is Akira's true identity is revealed.
 * Although it was kind of obvious to the players: she has a very feminine voice, and if I recall right one of her costumes has her without her helmet on, where you can clearly see she's a girl.
 * That's a bonus version of Akira which you unlock after beating the game with the good ending (notably, in the usual slide show during the credits, she is seen helmetless with her Gedo schoolmates, but if the player didn't get said good ending, they'll probably be left clueless, as in "who's that girl? where's Akira?"). Which is interestingly inverted in Project Justice: she starts off helmetless (due to It Was His Sled), and her helmeted costume (labeled "Powered Akira") is the unlockable one.
 * King in the first Art of Fighting game nearly pulls this off despite not wearing an actual disguise. By finishing her off with a special move in the last round, the player can blow her shirt open and expose her bra. In the second game and The King of Fighters series, King's true gender is an already known fact.
 * Captain Syrup from the first Wario Land is a villainous example; the game's instruction manual even refers to her with masculine terms to avoid ruining the surprise.
 * Although if you didn't read the manual, this one was pretty much lost on you, since she doesn't appear in-game until you fight her.
 * Faris of Final Fantasy V. Although she seems to pass for male strictly because she says so, as she's pretty enough for Bartz and Galuf (dueling Bobs) to swoon over her sleeping form, still thinking she's a he. This, of course, leads to Gilgamesh's classic line in the GBA Remake: "And now we will fight like men. And ladies. And ladies who dress like men."
 * This is more a failed attempt at pulling a Samus Is a Girl due to their choice of Super Deformed graphics. Yoshitaka Amano's original designs for Faris depicts her in a very masculine, yet feminine fashion.
 * On the other hand, pretty much all of Amano's original designs are kind of feminine.
 * The FMV for the remake follows Amano's design very closely, so it can't be completely attributed to Amano's artistic style. She could pass for a guy if it weren't for her coat being tight enough to clearly show she is female. On the other hand, outside her crew, virtually no one would get close enough for obscuring her figure to be required.
 * This is the main twist in the ending of the iOS edition of Dead Space.
 * A developer's choice of words during an interview has added more fuel to the fire on this trope being employed with the Pyro from Team Fortress 2.
 * Valve has seemingly been encouraging this from the beginning, with this trading card for the Pyro and the purse in the Pyro's locker. When one consider that the other 8 player classes (in other words, every character excluding the Announcer) are unambiguously men, it makes sense that they would play with The Unseen.
 * Some say the Pyro has a flowery purse because he's just a flamer.
 * A check of the voice acting credits for the game reveals that Pyro's unintelligible ranting is voiced by Dennis Bateman, who is definitely male. Whether this is deliberate obfuscation or not will probably only be resolved when Valve gets around to releasing the "Meet The Pyro" video.
 * To add another level of confusion, Dennis Bateman also voices the very definitely male Spy.
 * Final Fantasy Tactics A2 plays with this in reverse. One of the recurring enemy characters is the Night Dancer, a Bangaa that looks, acts and is referred to as being a girl, but the fight against her has a Law in place forbidding harming the opposite sex, setting up a potential hazard for the player who does not understand the difference between gender and sex.
 * Lampshaded by an NPC who is confused on what gender the Night Dancer is and another NPC refers to the character as an old man.
 * Wouldn't be the first time. Final Fantasy Tactics had the infamous(?) cross-dressing Time Mage. Someone put a one where a zero should have gone, metaphorically speaking.
 * In the original Final Fantasy Tactics
 * Toby Masuyo in Baraduke predates Samus by about a year (Although the fact that the game calls her "Kissy" is a bit of a giveaway). Her next appearances in the Mr. Driller series and Namco X Capcom do not play with this trope, opting to have her helmet-less (she's Mr. Driller's mom after all).
 * Happens twice in Tales of Vesperia. The first is with Yuri's pursuit of "Mr. Mordio" -- which turns out to be a Rita Mordio; the second is with the mysterious (and kickass) Dragon Rider -- which turns out to be . In both cases, Yuri winds up the "Bob". And in both cases, they remain a full-fledged mage and warrior, respectively.
 * In his defense "Mr. Mordio" clearly has a mustache, and had to have been seen to do the job he was contracted with. It's just he was using someone else's name. Played straight when you reach Aspio and everyone refers to Mordio as "that person" or "that weirdo".
 * The Cyborg Ninja in Metal Gear Solid 2 is not Gray Fox as in the first game, but instead
 * In a way, this happens
 * The last target in Assassin's Creed is not there when you go to kill him.
 * The Power Armor in the Fallout series has always been gender neutral, but hearing a female voice from the Power Armor speakers in Fallout 3 caused players Samus Is a Girl spit-takes (and demand from female players for more feminine and form-fitting Power Armor mods).
 * Before then, most power-suited Enclave soldiers in Fallout 2 were actually female. Even some that you spoke to.
 * in Persona 4. With the twist that the party finds out when they show up to rescue her, rather than her rescuing them.
 * Somewhat frustrating, as you can hear feminine tones from the moment you see her (in the American Version), but the game will force you to play along with it until . This can lead to the player screaming.
 * Needless to say, the Japanese version is much more convincing, if only because her voice actress has done male roles before (she did Edward Elric).
 * Also the case with . This one is done quite a bit better, which makes it sort of puzzling why they didn't use her voice actress for.
 * Portal plays with this, in that the main character is female, but there's no indication of this until you happen to get a good look at yourself through a portal. While you can clearly see yourself in the very first portal you step through, it's hard to tell that it's you right away. In the sequel, Wheatley passively assumes that whoever beat GLaDOS was a guy, and is taken aback when he finds out that it was you.
 * The first Destroy All Humans! revealed that Majestic-12 leader Sillouette is a female at the end, though you can learn this earlier on if you read the thoughts of a Magestic agent, which you might just ignore.
 * Metal Gear Solid does this with Meryl, who "disguises" herself as a male soldier, though it's really only because all the uniforms look more or less exactly alike.
 * Word of God states that this was to have been the big reveal at the end of the fifth game in the old ZX Spectrum Magic Knight series (Finders Keepers, Spellbound, Knight Tyme, Stormbringer and...). Possibly Older Than the NES, possibly not (the first two games both came out in 1985, and the first game definitely refers to Magic Knight as 'he', so it may not have been planned at that point).
 * In the first Tekken, Kunimitsu was simply a palette swap of Yoshimitsu, with the same voice as well. In the second game, the character was revealed to be female.
 * Although it has to be said, she was always meant to be female, as you can see in concept art. 3D graphics weren't that good at the time of the first Tekken, however.
 * And there is also Leo from Tekken 6, who is widely believed to be a woman dressed as a man, or a gay male. Namco have deliberately not confirmed either way, stating they wanted to create a character who could be "loved by either gender".
 * In the game by Tim Schafer, Brutal Legend, Eddie, the main character, fights many demonic druid enemies in robes, and then faces one of them head on. In the middle of the fight, that "evil druid" flips off her hood to reveal that this is, in fact, a female human. Eddie the remarks, "Oh no, don't tell me I've been slaying hot chicks this whole time."
 * At the end of Dragon Warrior Monsters, the
 * Hooktail, the boss of the first level in Paper Mario: The Thousand-Year Door, is assumed to be male by all characters (and described with male pronouns in Goombella's Tattle), until the final chapter, when you meet Gloomtail in the Palace of Shadow. When your partner asks what Hooktail is doing here when you've already beaten him (as Gloomtail is essentially a palette swap of Hooktail), Gloomtail becomes furious upon learning what you did to his precious baby sister. Tattling on Gloomtail elicits a hilariously shocked reaction to this revelation from Goombella.
 * The third Sly Cooper game gives us
 * The mysterious scrambled voice in the marine campaign in Aliens vs. Predator 2, though she never actually does any fighting.
 * Black Widow from Ring of Destruction: Slam Masters II, is a somewhat effeminate wrestler who is taller than most of the other wrestlers in the game and whose spider-themed costume covers his whole body. If you beat the game with him, Widow reveals herself to be a tall and muscled female wrestler.
 * Around half-way through Ratchet and Clank Going Commando, the thief you have been pursuing is unmasked to reveal that she is female, to Ratchet's surprise. This also marks the point at which she stops being an enemy, but more because they were betrayed by the real villain.
 * Junon from Dragon Force pulls this one on everyone in her world until her helmet gets knocked off during an encounter. She's the one in the badass black armor. She's also #139.
 * from Baten Kaitos.
 * The video game series Guilty Gear is notorious for pulling off a reverse of SIAG (Bridget needs no introduction), but what many people don't know is that Word of God has stated that Justice, the final boss of the first game, the Commander Gear, a large, powerful robot-type person with a noticeable crotch spike, is really a female and was a dear friend of Sol Badguy's.
 * from Dragon Age: Origins is
 * Her Voice is obviously female, and if you keep them both in the party she flirts with Sten constantly.
 * In Mirror's Edge, Faith spends part of the game chasing after . Much later, when Faith gets into combat with, it is revealed that.
 * in Mass Effect 2. She's never actually physically disguised, but all you know before meeting her is that she has a Tomboyish Name and a nasty reputation. This reveal was spoiled in the advertising.
 * Chris from Princess Waltz is taken to be a man by the main character. Even despite many hints and on mutiply occasions fusioning together to become a woman, the main character doesn't realize that Chris is actually a girl untill... well... Either way even the main character feels stupid for not getting the hint before.
 * The sequel to Crystal Quest reveals your Flying Saucer -- depicted in gameplay as a 16-pixel-wide circle -- to be piloted by a space cow with six legs (who is, of course, a girl).
 * from Dark Cloud 2 first appears disguised as a young child when you first meet her, and after, removes her hood and reveals herself to be a woman.
 * of Valkyria Chronicles II. Her voice kinda gives her away, quite a few players were still confused by the fact the game's encyclopedia classifies her as male, and that she has a male character model in game.
 * Julian from Growlanser. Her portrait is a giveaway when you first meet her as an Imperial Knight (you can see she has cleverage if you examine closely the portrait where she hold her sword) It was stated that Imperial Knights does not allow females to join, thus she hid her gender (though her 2 fellow companions Oscar and Lyell already found out and choose to ignore).
 * Jayle from Valkyrie Profile. A noblewoman Jeanne D'Archetype who disguises herself as a man in order to join Gerabellum's order of knights. Only her commanding officer knows of her disguise but says nothing about it, as he's fallen for her.
 * In Disgaea 2 Cursed Memories, everybody assumed Overlord Zenon is a male, but turns out, though.
 * Note that is very clearly female. This is more of a case of The Girl Is Samus.
 * Subverted in Hydorah. Throughout the game, the player character is conspicuously helmeted, but is revealed in official artwork to be
 * Dragon Fable has Vilmor. She was assumed to been a male not only by the PC, but also by a majority of the players, despite obvious hints early on into her storyline. Was even referred to as male in a Newsletter.
 * The player character of Faria is only represented by an androgynous Super-Deformed sprite, and gender is not revealed until after she's saved the princess.
 * Subverted with Alex Wesker in Resident Evil 5's DLC "Lost In Nightmares." Fans initially assumed that Alex Wesker was likely to be female due to a lack of third person gender identifiers in the memo revealing Alex's existence. However, the lack of gender pronouns was in fact the result of a shoddy localization attempt by the localization team. In the Japanese version, it is made very clear that Alex is male.
 * In Fire Emblem Awakening, there's a masked swordsman/AntiHero who shows up early in the game, Marth. Previous incarnations of that Character have been, while some what Androgynous, but definitely male... Turns out "Marth" is actually Lucina, Krom's time-traveling daughter... The Reveal is actually quite touching.

Visual Novels

 * Inverted in Fate/stay night. Lady of War Saber is obviously a female knight, but it isn't until later on that we learn she is actually, who used magic to disguise herself as a man because
 * Fate Nuovo Guerra follows tradition and chocks one up with a certain Lancer from The Trojan War, though it wasn't so much a disguise as it was "sexist historians" who didn't like how a girl was getting all that booty and kicking all that ass.
 * Phoenix Wright: Ace Attorney: Justice for All: Phoenix doesn't learn Manfred von Karma's child's gender until facing her in court.
 * In what is most likely an oversight, Phoenix refers to Engarde's manager correctly as a "she" during the initial interview, despite having no information on his manager beyond her existence.
 * This was most likely due to the manager's name being very gender ambiguous, which plays a key role in the case and was something the writers intended.

Web Comics / Web Original

 * Miko Miyazaki from The Order of the Stick does this. For about eighty or so strips, she appears only as a blue-hooded figure, until she takes on the Order of the Stick, at which point she drops her hood and we see that yes, she is in fact female (and, judging from Roy's reaction, fairly attractive). Roy plays her Bob for a while, until he gets put off by her personality. This wasn't that drastic, as she seemed more ambiguous than masculine prior to this.
 * Before The Reveal, she doesn't even seem to be human.
 * Also initially appearing as a hooded figure was, Miranda West of The Wotch. Her initial appearance was in the very first story arc. Her reveal was at the end of the fifteenth.
 * from Inhuman is shown to be an example of this when another character walks in on her changing.
 * Peregrine Mendicant of Homestuck. The author never intended her to actually have a gender at all, but gave in to fan speculation.
 * Pratos the Bounty from Jix ends up being both a female Ambis named Aranis and Jix's cousin. A possible nod to Samus Aran.
 * Jix herself was thought to be male until her brother Romulos revealed her true identity (it's hard to tell what gender a small furry alien is unless you are able to see anything).
 * from A Modest Destiny. She spends a good amount of time in the comics as this until an incident where Maxim grabbed her breast, and it's not shown who she is until much later.
 * When the previously killed Crimson Blade shows up at the Vampire Lord Fluffy's castle, Fluffy's bat familiar flies off with the helmet, revealing that the new Crimson Blade is a girl. Expecting this trope, Fluffy immediately tries to hit on her, but actualy fails miserably.
 * in the Halo Machinima series Red vs. Blue: the Blood Gulch Chronicles.
 * In a semi-aversion of the usual way this trope is carried out, even after The Reveal her appearance is never feminine in any way. The sole differentiating factor is really her voice.
 * in the Halo Machinima series Spriggs.
 * Hilariously parodied in The Onion: "Hotshot Test Pilot Removes Helmet, Reveals Female Status".
 * in Dragonball Z Abridged. Much to Vegeta's horror and disgust.
 * This Interrobang Studios comic where Luigi complains to Link about some gay Bounty Hunter in Orange armor who asked him out.
 * Gunnerkrigg Court: The interim comic City Face 2 introduces a magpie named Bobeyes. In a bit of Painting the Fourth Wall, the Shout Box below the comic features commentary by in-universe characters - one of whom is a magpie going by the username "magpie55". He thinks Bobeyes is a pretty cool, tough guy, and is as surprised as anyone to learn that Bobeyes is a girl. From his commentary on the final comic page, it's obvious that he's smitten.
 * Inverted in Hanna Is Not a Boy's Name's first two strips, as {...} naturally assumed that "Hanna Cross" would be a woman. Played straight a short time later when bat!Adelaide was introduced.
 * In the fifth season of The Guild,  are revealed as hot girls.
 * Cordell the dark elf from Gaia Online was not particularly concealed, just androgynous, having been introduced as a champion of the dark elves willing to compete in the (non-canon) Reject Olympics on behalf of Durem. She was found to be female when an aggressive Yaoi Fangirl invaded the track and felt her up. "Hay UR not a bishie!"

Western Animation

 * Sarasim in the Teen Titans episode "Cyborg the Barbarian". Cyborg is her "Bob."
 * In the 2003 Teenage Mutant Ninja Turtles 2003 series, the turtles meet a lithe blue mutant called Quarry, leader of a pack of formerly human test subjects of Shredder's weird genetics experiments. When the turtles are able to find a (range-limited, at first) cure, it is revealed to their surprise that Quarry is a woman.
 * Helped along even more, is the fact that they watched a video where they see a man strapped to a table and turned into something that looked like Quarry.
 * The X-Men: Evolution version of X-23 isn't revealed to be a girl or a young teenager initially, though she did look awfully small for a ninja/secret agent/whatever she was supposed to be disguised as.
 * Parodied by Quackor (The Foul), the Evil Counterpart of (Dial "M" For) Monkey in Dexter's Laboratory.
 * In The Flight of Dragons, the animated movie loosely based on the book by Peter Dickinson, the band of heroes is saved from a pack of thieves by a Robin Hood wannabe. When the knight in the group goes to thank the mysterious archer, "he" takes off "his" cap, and the audience is treated to a slow-motion shot of long, glistening, red hair as it flows down below her waist. The knight is speechless.
 * SpongeBob SquarePants parodied this trope, when Sandy Cheeks took off her diving suit in one episode. Patrick exclaimed in shock "Sandy is a girl?!" although everyone in Bikini Bottom should be more than just aware, that Sandy is female. In fact she's very popular with the towns boys.
 * Played more straight in the medieval episode.
 * In an episode of Family Guy, Chris is conflicted over kissing a friend named Sam... Until he finds out she's a girl.
 * Another episode features a talk show where it's revealed that a girl's boyfriend...
 * In the second season of Wakfu, ends up as this.
 * The Simpsons parodied it in Homer Of Seville when Homer was being chased down by a horde of rampaging Opera fans (It Makes Sense in Context) and was saved by a helmeted motorcyclist dressed in black leathers. When the errant saviour takes off the helmet she says "That's right I'm a woman" in a What Do You Mean It's Not Awesome? overdone way before Homer remarks in stilted speech "A lady motorcycle driver. What is this, The Twilight Zone?".
 * An old Looney Tunes cartoon features Daffy forming a rivalry with a small duckling. He realizes he can't bring himself to hurt someone that small, so he uses Phlebotinum-powered growth pills to force the duckling to grow to his size... only he can't bring himself to hurt her after that, either. There are other things he can bring himself to do with her, though...
 * In The Grim Adventures of Billy and Mandy, Mandy does a classic by pretending to be a boy on Billy's baseball team, Billy believing girls can't play baseball even though Mindy has a team of her own (which she uses to beat them silly twice).
 * Danny Phantom had one episode that involved a video game which Danny and Tucker are wrapped up in but can't defeat a gamer who constantly outwits them at every turn. Near the end of the episode they find out the gamer is Sam, which is practically humiliating as earlier in the episode they mocked Sam thinking due to a girl, she wasn't good at gaming. So her smugness in the reveal is justified.
 * Avatar: The Last Airbender has Smellerbee who was dressed like a boy and, despite having a girl like voice, made it hard to tell which gender she was. It wasn't until "The Serpent's Pass" episode when Jet's group meet Iroh and Zuko that her gender is revealed after Iroh mistakenly classifies her as a boy and she angrily corrects him.
 * Also the episode "Warriors of Kiyoshi". Sokka is surprised (to say the least) to find out that it wasn't men who ambushed them but a pack of teenaged girls.
 * For the viewers, a good chunk of the Fire Nation army, if Zhao's speech in "The Blue Spirit" is anything to go by ("We are the sons and daughters of fire, the superior element!")
 * On an episode of a Saturday morning cartoon based on Raggedy Ann and Andy, Ann and Andy get rescued by a helmeted, laser toting space warrior. Warrior turns out not only to be a girl but a princess.
 * Arguably, Flaky. Word of God States she is, in fact, a girl.
 * One of the Main Villains of The Condor Taipan is revealed to be Helped by the voice distorter and masculine nature of her costume.
 * The Super Mario Bros Super Show had a Zorro-themed episode, where the Zorro Expy turned out to be the waitress from the local cafe, who's exposed at the end of the episode when she forgets to take off the fake mustache.
 * Futurama Leela did this, but with a Paper-Thin Disguise, so only other characters where surprised.

Other

 * Used in a Finnish ad for the army, where paratroopers are making a training landing in a forest and It's Raining Men plays. The song cuts when the troopers remove their helmets, revealing that they are all women.
 * Another commercial for a high-grade beer shows the hands of the brewmaster at work, as the narrator praises the skill of those hands. At the end, the narrator says that they're focusing on the brewmaster's hands because she's not a particularly-attractive woman.
 * Chevalier d'Eon kept people guessing until the very end.
 * As it turns out, at least biologically speaking s/he was male, though it's possible that s/he was an early example of a transsexual.
 * Sadly, in real life no ghosts were involved.
 * There was a stagecoach driver in the American West named Charley Parkhurst. One-eyed Charley was known for his toughness and could handle anything, up to and including armed bandits. After his death (at age 67), the person who laid him out discovered "Charlie" was a woman, and her birth name turned out to be Charlotte.
 * A tribute of sorts is given in the second and fourth Blackadder series, where a girl named Kate pretends to be a young man named Bob Parkhurst.
 * A similar discovery was made about jazz musician Billy Tipton (nee Dorothy Lucille Tipton), following "his" death. Even "his" adopted sons and at least one sexual partner didn't know "his" true gender.
 * Lots of people tend to call unfamiliar dogs "boy" on first sight, assuming they're male until proven otherwise.
 * My God! It's a Woman, the biography of Australian aviatrix Nancy Bird.
 * The Science Fiction author James Tiptree Jr. was discovered, after much controversy and one prominent author penning an essay on how it was impossible and inconceivable that James could be a woman, to be a lady named Alice Bradley Shelton. The fact that she wrote many stories where gender took a major role did not help.
 * George Sand, birth name Lucile Dupin, also qualifies.
 * J. K. Rowling. Apparently, some people were surprised to learn the real name. This was deliberately invoked by the publisher because their initial target audience was young boys who they felt might be put off by a female author.
 * This is pretty common with female authors who write outside traditionally "feminine" genres. S. E. Hinton. K. A. Applegate. C. J. Cherryh.
 * In the olden days, women who ran businesses would often take advantage of this or run the business through their husband, the legal owner.
 * Inverted after Equal Rites, where many assumed Terry Prachett to be a woman based on the book's feminist themes.
 * This Red Bull ad, the biker is a woman. And deaf.
 * Jack Prelutsky's children's poem "The New Kid on the Block" describes the titular new kid as a terrible bully who "likes to fight and picks on all the guys"; and ends with the line, "I don't care for her at all".
 * A beautiful real-life example, except for the fact that it says "Samantha" on the side of the cockpit.
 * Gender Flip: The video "It's Time", shot from the perspective of someone who falls in love with a man and builds a relationship with him. The video ends with the man proposing marriage, and the camera pulls back to reveal that the point-of-view character was another man this whole time. The video was heavily promoted by gay marriage advocates, causing many people to not even realize that the POV character's gender was supposed to be a Twist Ending.
 * Real Life example: In the 2012 Orange Bowl, a West Virginia player celebrated by tackling the Orange Bowl mascot. This is his reaction upon learning that the mascot was played by a woman.