Examples of Samus Is a Girl in live-action movies.
- In Slasher Movies featuring female killers, the villain's gender is usually hidden by either a disguise/mask, camera angles, Murderer P.O.V., or some combination of the three. Plus, they're probably played by random stuntpeople up until The Reveal.
- 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?"
- Barbarella in the beginning of the original film, where a bulky spacesuit is removed, and fanservice ensues.
- This seemed to be the idea behind Nyssa's first scene in Blade II. 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.
- In Colombiana, the police assume that Cataleya's murders were performed by a man, with the lead detective scoffing at suggestions that the killer is a woman because "they had to have been performed by someone with great size and strength". Cataleya uses Waif-Fu to kill.
- A racial version occurs in The Crazies (1973). The sheriff and mayor are startled when the colonel in charge of the Gas Mask Mooks removes his Hazmat Suit to reveal he's black.
- In The Dark Knight Rises the audience (and Batman) is led to believe that the child who escaped from Hellhole Prison was Bane. It turns out that the child was actually Talia, the daughter of Ra's Al Ghul, with her gender deliberately made ambiguous by her short hair and the narration just referring to her as "the child",
- The Blank / Breathless Mahoney in Dick Tracy. The Reveal is actually quite a Tear Jerker.
- In Dirty Rotten Scoundrels, main character and lovable con artist Lawrence Jamieson hears rumors of an infamous grifter known only as "the Jackal" infiltrating the French Rivera, where he pulls his cons. He soon suspects that Freddy Benson, a small-time crook from the United States, is actually the Jackal operating an assumed name. This development is largely forgotten after the main plot arises: Lawrence and Freddy competing to scam American heiress Janet Colgate out of fifty thousand dollars, and later trying to be the first man to win her heart instead. At the end of the movie, both men have chosen to let her go...which is when she reveals she's conned both of them out of $50,000 each—Janet was the Jackal all along. The movie ends with the three teaming up to con even more wealthy fools out of their money.
- Humorously done in Doctor Strange, as when Strange first enters the school of the Mystic Arts he addresses a Fu Manchu-esque monk as the Ancient One only for the monk to leave the room and the bald lady who was serving Strange tea to reply and reveal herself as the Ancient One. Some fans also muse it was kind of a Take That! at the comics' outdated Yellow Peril stereotype of the Ancient One.
- Dragonslayer: Valerian turns out to be a woman, which Galen is surprised to find out after diving underwater into the river when she's bathing (despite her protest). It turns out most of the villagers knew already though.
- In Eden Log, the botanist turns out to be a woman when the man removes her helmet.
- In Fanboys, the main cast is horrified to learn that one of their closest and most valuable contacts for information, "Rogue Leader", is actually a 10-year old girl. Needless to say, her uncle is not too happy with them talking to her.
- Downplayed in The Fifth Element - the scientist who revives Leeloo assumes that the "perfect" alien he's rebuilding in human shape will be male ("Can't wait to meet him!") He isn't visibly disappointed when he gets an Action Girl (It is Milla Jovovich, after all).
- Full Metal Jacket: The Viet Cong sniper is a young woman.
- In Godzilla: Final Wars, Ozaki is assigned to bodyguard a professor who is going to examine a fossil in a remote location. Ozaki starts complaining about having to escort some old coot around, only to be pleasantly surprised when the professor is revealed to be a woman who looks like a model.
- 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.
- 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 a young boy. This may have been an homage to the infamous use of the same variant in the opening scene of Halloween.
- Shura spends the vast majority of her time in Hussar Ballad wearing hussar uniform, and every time some other character learns that she is actually a girl, it causes a lot of surprise and disbelief.
- 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". Which could qualify as this.
- In Indiana Jones and the Last Crusade, Marcus Brody and the title character are somewhat surprised when they learn that their Austrian contact, Dr. Schneider, is actually a woman—her first name turns out to be "Elsa".
- The opening scene of Iron Man has Tony exclaim in surprise when he realizes that one of his three military escorts is actually female (she's wearing BDUs, ballistic armor and a helmet, so it's hard to tell). She's revealed by her feminine voice the first time she speaks up.Tony: Good God, you're a woman! Good God. I honestly, I couldn't have called that. I mean, I would apologize, but isn't that what we're going for here? I thought of you as a soldier first.
Ramirez: I'm an airman.
Tony Stark: Well, you have actually excellent bone structure there. I'm kinda having a hard time not looking at you now. Is that weird?
- Jet Pilot (1957). A Soviet jet fighter is forced down on an American base. John Wayne is flummoxed when the pilot removes her flight helmet and oxygen mask (with requisite hair flip) to reveal a gorgeous Janet Leigh.
- Everyone in Camelot is taken by surprise when the Black Knight, a mysterious figure in A Kid in King Arthur's Court, reveals that he's actually Kate Winslet.
- In the film The Last Legion, familiarity with those trope allows one to quickly surmise that the Eastern Roman Empire soldier is a chick. Why else would she wear a helm with an aventail like that?
- In the 90s The Little Rascals movie, the boys are all excited about meeting a NASCAR driver by the name of A. J. Ferguson. They assume A. J. is a man, because in their minds, there's no way a girl could do something cool like be a racecar driver. (And also not too many women go by their initials.) When they finally meet A. J. Ferguson, "he" takes off his helmet, only to reveal that "he" is actually a very beautiful woman. The boys are speechless initially, but they are still excited.
- 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."
- Momentum (2015) opens with a bank robbery committed by criminals wearing armoured outfits and voice distorting masks. During a struggle their leader's mask comes off to reveal Olga Kurylenko. Somewhat expected given she's the lead actress, but her gender is well concealed prior to the reveal.
- In Pitch Black, the teenage boy "Jack" is revealed by Riddick, at a conveniently inappropriate moment, to be female. It turns out the blind creatures hunting them are tracing them by their scent of blood, and, although no members of the party appear to be wounded, "Jack" is menstruating.
- Pocket Ninjas when the White Dragon at the fight scene near the end was revealed to be Tanya.
- Maid Marian's initial appearance in Robin Hood: Prince of Thieves, followed shortly after by Chickification.
- At the beginning of The Scorpion King, Mathayus, along with his his half-brother Jesup, and friend Rama, are mercenaries hired by King Pheron to assassinate Memnon's sorcerer, after Pheron learns that the tyrant's victories are a result of the sorcerer's ability to see the future. However, after a difficult infiltration (where Rama is killed and Jesup is murdered), Mathayus discovers that the sorcerer, who he presumed was a man, is a woman named Cassandra. (Who later rescues him and changes sides.)
- Related to the above, as Ghostface's trademark in the Scream films (and the TV reboot) is to make Harassing Phone Calls to victims, they always use a voice-changing filter to give themselves a deep, threatening creeper voice. This has allowed three women (Mrs. Loomis/Debbie Salt in the second film, Jill Roberts in the fourth, and Piper Shaw in the TV show's first season) to don the mantle of Ghostface over the course of the franchise.
- 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.
- Sky High (2005): Power-armoured supervillain Royal Pain turns out to be Gwen, the girl that Will has a crush on. The weapon she built before being defeated by Will's superhero parents turned her into a baby, and her henchman raised her. Lampshaded by both the villain herself and her nemesis, the Commander.Commander: Royal Pain... is a girl?
Royal Pain: Yes, I'm a girl, you idiot!
- In The Son Of Robin Hood, Little John has a problem with Robin's heir. Three guesses to what it is.
- Star Wars:
- Boushh is Leia disguised as a bounty hunter with a voice-altering mask.
- 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.
- Captain Phasma in The Force Awakens wears the standard Stormtrooper armor, albeit a more decorative one indicating rank, but then speaks in a clearly female voice. In addition to her, one of the regular Stormtroopers also clearly has a female voice, implying female soldiers are a normal thing among the First Order (and possibly were in the Empire).
- From the same film, Rey is initially introduced wearing loose clothing and headgear that make it difficult to tell that she's female.
- In the anthology film Solo it's revealed that Enfys Nest, who wears gender-obscuring armor and uses a voice filter, is a very young woman allied with the nascent Rebellion.
- 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 The Sting, the hitman "Salino" turns out to be Loretta Salino, the waitress in the diner.
- When Hondo and Street go recruiting for Hondo's new SWAT Team in S.W.A.T., Canon Foreigner "Chris" Sanchez is found at the hospital after having beaten the crap out of a Gang Banger. Hondo is very surprised to learn that Sanchez (played by Michelle Rodriguez) is a Spicy Latina a good foot-and-a-half shorter than him.Hondo: Sorry, wrong room.
Sanchez: Who were you looking for?
Hondo: Chris Sanchez.
Sanchez: I'm Chris Sanchez.
Hondo: You're Chris Sanchez?
- Ted Bundy: The executioner wears a mask. When Ted is dead, she takes it off.
- 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.
- In the Vincent Price film Theatre of Blood, Lionheart's lead henchman the British accented guy with the hippie glasses, afro, and beard turns out to be his daughter Edwina (Diana Rigg).
- 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.
- 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.
- 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 Your Highness, the heroes meet a mighty warrior in the arena, and are surprised when she removes her cloak.
- Comes up early in Zero Dark Thirty as one of the spectators to the torture is revealed to be female, hidden by a hood.