Mal: Tactics, woman. Needed her in the back. Besides, them soft cotton dresses feel kinda nice. There's a whole... airflow.
Inara: And you'd know that because...?
Mal: You can't open the book of my life and jump in the middle.
See that harmless little lady over there? She's actually a man — a masculine, adventurous man who uses the dress to appear harmless and hide in plain sight.
Men are active, women are passive. That's the way things are, at least according to traditional gender roles.
Thus, if a man wants to become invisible and appear nonthreatening, it can be beneficial for him to pretend to be a woman. In sharp contrast to most forms of regular cross-dressing, this is done as a way of avoiding attention.
Contrast Sweet Polly Oliver, which is something of the inverse of this trope, since those women dress as men in order to openly embrace the male gender role of being active and potentially dangerous.
Many of the examples specifically have a male character disguising himself as an old woman, which is somewhat less reliant on sexist perceptions since senior citizens are (stereo)typically weak and frail (and it's also somewhat more believable that a man could look like an older woman than a younger one).
- In The Crunchie Train Robbery, when the outlaws emerge carrying the strongbox full of Crunchies, a respectable looking matron jumps up. whips off 'her' wig and rips open 'her' dress to reveal a marshal's badge.
- In the "Moonlight Sonata" arc in Detective Conan, after a young boy named Seiji Asou escaped the strange death of the rest of his family because he was hospitalized in Tokyo, he was adopted by an old friend of his dead family (which let him stay unnoticed), and grew up into a handsome (and girly-looking) doctor. He then returned to his island under the false name Narumi Asai (not totally false, actually)—as a female doctor—to investigate their murders and have his Revenge. He got away with almost all of it, confronting and then killing all the culprits while leaving strange music-related messages... but when he was caught by Conan, Seiji set his family's old house on fire and stayed inside as it burned down, calmly playing the Moonlight Sonata in his father's old piano despite Conan's desperate pleas for him to live. Note: he, like most villains in the series, was portrayed with so much sympathy that viewers would, at worst, consider him an Anti-Villain. Strangely, in Italy, due to homosexual connotations, the trope wasn't spelled out (but still implied) to get it past the Media Watchdogs.
- In Fullmetal Alchemist, Roy runs into a kind old lady at a cemetery—who, it turns out, is actually Lt. General Grumman.
- Joseph Joestar of JoJo's Bizarre Adventure disguises himself as a lady in order to get inside a Nazi compound. It doesn't work - he's over six feet tall and has the build of a professional wrestler. The Nazis take one look at him and ready their guns.
- Joseph gets the "tequila" outfit as an alternate costume in JoJo's Bizarre Adventure: Eyes of Heaven, with him claiming that he's trying to pull this routine on their opponents. Most of the cast has special dialog where they tell him what a poor disguise it is or call him a creep; amusingly, Polnareff points out the obvious flaw in the disguise (the whole "six feet tall and beefy" thing) and Joseph's reaction is "OH NO! I didn't even consider that!"
- During Rei's introduction in Fist of the North Star, he's disguising himself as a helpless woman with a cloak in order to attract bandits and kill them for their food.
- Madam Fatal, a 1940s superhero, had this as his shtick, earning him a spot on Cracked's 7 Crappiest Superheroes.
- Batman did it in Batman: The Dark Knight Returns, as an old female customer at a liquor store.
- A mob boss "disguised" himself as a woman for years to avoid being killed by The Punisher. His nephew later joined him out of fear of the same fate.
- Early Captain America disguised himself as a grandmother and Bucky as a small child and then going to Nazi-occupied France.
- Obscure villain He-She has the left side of a pretty woman, and the right of a tough man. His/her entire strategy for dealing with heroes is to turn so that only the female side is visible, thus making people think that he/she is weak like a woman and either harmless or needs protecting. Yeah.
- Judge Dredd: In one story the undead superfiend Judge Death escaped from his confinement and murdered an old woman to use her dead body as a disguise. Though he really wouldn't be able to pass for human if someone took a closer look at him.
- In Robin a grounded Tim who cannot get out of the house without his dad noticing spots an internationally wanted criminal who dresses up as a pregnant woman and then leaves as one of their own hostages on a breaking news segment. His frantic hushed calls to the rest of the Batfamily result in the crook's capture when he pulls the same stunt to try and escape the police in Gotham.
- At the end of Mulan, the villain has the place guarded to stop any soldiers coming in to save the day, but a few of Mulan's male colleagues talk their way in, disguised as concubines. Ugly concubines.
- In Open Season 2, Elliot (who is a deer) dresses up as an old lady to get pass security to the pet camp where he thinks Weenie is being held prisoner. Somehow the man watching for trespassers completely falls for it, even mistaking another old lady (who was wearing the same attire as Elliot's disguise) for the culprit.
- Madmartigan's lady disguise ends up serving as this in Willow when the villains are searching the town he's in. It doesn't fool them for long, though...
- Agent Smecker in The Boondock Saints dressed as a tartish woman to get through a mobster's defenses (and it's implied to get through their pants as well.)
- Eames, The Forger, does this in Inception to distract Fischer while Cobb brings him over to their side. Unlike most of these examples, he uses illusion rather than a physical disguise.
- Used by the villain of The Devil-Doll to bluff his way through encounters with his intended victims and the police, and also as an excuse to carry around his "dolls" (actually miniaturized assassins) in public.
- The existence of this trope in the popular imagination winds up getting the protagonist of Breakfast on Pluto (a possibly transgender Wholesome Crossdresser) in a lot of trouble. Kitten is not a violent person at all, but when a nightclub she visits is bombed, the authorities suspect that the biologically-male Irish person in women's clothing is an IRA operative, and she's arrested and treated very badly.
- In the Jim Belushi comedy Taking Care of Business, Jimmy Dorsey disguises himself as his own mother to break into a prison. It somehow works.
- In both the silent and talking versions of The Unholy Three, Lon Chaney is a criminal and burglar who disguises himself as a sweet old grandma as part of a complicated plot to gain entry into the houses of rich folks.
- Subverted in Suffragette; one of the suffragists, who is actually a woman, disguises herself as harmless lady by using a baby carriage to hide the brickstones she's going to smash windows with.
- The Swedish criminal Folk Hero Lasse Maja used this extensively. (Lasse is a traditional Swedish male name, and his real name. Maja is a traditional Swedish female name, and the nickname he used. It appears he was not a cross-dresser otherwise, he only used his female persona to carry out his schemes.)
- In one ballad, Robin Hood was nearly cornered when he exchanged clothes with an old woman. She was captured by the sheriff; he got away and brought his merry men to face down the sheriff.
- The Scarlet Pimpernel is famous for this, and probably the trope maker.
- In G. K. Chesterton's The Club of Queer Trades, a curate describes a gang of criminals dressed up as a group of respectable old ladies. Subverted, in that the "curate" himself is lying and in disguise.
- In Dorothy L. Sayers' Lord Peter Wimsey story, "The Article in Question, a lady's maid turns out to be a disguised male criminal. The noble lady employing the 'maid' is less than horrified to discover she's been dressed and undressed for the better part of a month by a young man. In fact she seems rather pleased.
- Starfighters of Adumar has the infamous "Escape Done In Drag". Wedge ordered his three pilots to get him four sets of women's clothing, in which they snuck into a base while a diversion went on. On Adumar, women can take all the combat positions men take, but Wedge and his pilots were male and being hunted by pretty much the entire city, so a group of four women would be less suspect. Hobbie cemented the disguise by doing a convincing scream.
- The Stainless Steel Rat once took several dozen army deserters through a military checkpoint dressed as women. On bicycles.
- In Harry Potter and the Goblet of Fire, Barty Crouch Jr. escapes Azkaban disguised as his elderly mother.
- In Monstrous Regiment, the soldiers attempt to gain access to a heavily guarded fortress by disguising themselves as washerwomen. Subverted in that all of the soldiers save the lieutenant are actually women...who just happen to be disguised as men. It Makes Sense in Context.
- In A Study in Scarlet Sherlock Holmes is fooled (for a while) by a man disguised as an old woman; he himself pulls off this disguise in order to trail a villain in The Mazarin Stone.
"He actually picked up my parasol for me once. By your leave, madame, said he - half-Italian, you know, and with the Southern graces of manner when in the mood, but a devil incarnate in the other mood. Life is full of whimsical happenings, Watson.
- In Michael Flynn's The January Dancer, near the end, Hugh at one point is disguised as a woman.
- In Fred Vargas' The Chalk-Circle Man, Augustin-Louis Le Nermord spends half his time dressing as an especially ugly old woman, which is part of his creepily elaborate plan to kill his wife.
- In the world of A Brother's Price women are the dominant sex and men are so rare it's unthinkably dangerous for one to go out alone. Men are also long-haired, makeup-wearing, and don less practical prettier clothing. However, whores in this world do themselves up to look like men and take on male mannerisms - so when Jerin has to go out, he masquerades as a whore.
- In Dragonlance: Dragons of Autumn Twlight, the male heroes disguise themselves as women to infiltrate the slave-mine Pax Tharkas. This causes some issues for Riverwind whose people have a cultural taboo about males dressing in female clothing.
- In The Invisible Library, the protagonist, who is a real woman, often makes use of sexist stereotyping in the worlds she visits to make herself seem harmless, often by combining her oppressed status as women in patriarchy with dressing as lower class (whether that is a disguise is questionable, as the librarians exist outside time and space and thus, any class system). In the first chapter, she is seen cleaning the floors of a school, which is part of a plot to steal a book from there. When traveling a patriarchal world with a new trainee, she pretends to be his secretary, but the resident Great Detective quickly figures out that she is actually the one in charge. There is also a villain who disguises as a woman by much more magical means.
- The Laundry Files. In a same-sex version, Mo isn't happy when she's picked for a covert assignment because she's a "woman of a certain age", so her superiors believe that no-one will be paying attention to her.
- In Doctor Who, the Second and Third Doctor have used these types of disguises. In Three's case, Captain Yates of UNIT compliments his handbag, and the Doctor threatens to slosh him with it (it's a bucket).
- Quark in the Star Trek: Deep Space Nine episode "Profit and Lace".
- An extreme example since Quark underwent surgical transformation rather than just donnin a disguise.
- Mal in Firefly pulled this stunt in one episode, pretending to be Jayne's wife.
Mal: I swear by my pretty floral bonnet I will end you.
- Used ad nauseam in 'Allo 'Allo!.
- The title character on Baretta frequently did this. A couple of them can be seen in the opening credits.
- In Hogan's Heroes, Newkirk occasionally utilizes a 'little old German lady' disguise to fool the Germans.
- The Lone Ranger disguised himself from time to time in order to reconnoiter; very occasionally he dressed up as an old woman.
- Hannibal once dressed as a nun on an episode of The A-Team.
- In another episode, he's dressed as a bag lady as part of a movie he's working on.
- In yet another episode, he pretended to be an old lady. More specifically, Murdock's mother.
- In another episode, he's dressed as a bag lady as part of a movie he's working on.
- Neville Savage of Mission Top Secret once disguised as an old lady with his accomplice pushing "her" wheelchair. It allowed him to pass under the protagonists' nose, but they later find the discarded costume.
- In an episode of Grounded for Life, Sean is unable to change a flat tire, so he wears a shawl and pretends to be an old woman while Claudia shows some leg to flag down another motorist to help.
- Robbie Rotten of LazyTown disguised himself as an old lady to give the hero a spiked apple and capture him.
- The first season of Bosom Buddies has two male characters dress as women so they can live at an inexpensive hotel for women.
- The Magician: In "Illusion of Black Gold", three bikers disguise themselves as old ladies to crash a funeral parlour and stage a kidnapping.
- Classical Mythology: Achilles' mother did this to him in an attempt to keep him from the war. Naturally, the plan fell apart when Odysseus presented all the girls he was hiding among with gifts and Achilles was the only one to immediately go for the sword.
- The Order of the Stick took this a bit further when Roy used a magical belt temporarily to turn female, in order to avoid some assassins, who, true to the trope, just assumed he was a prostitute and ignored him — except for the dwarf, who invited him up to his room. That bit didn't end well for anyone involved. However, while their assumption falls under this trope, Roy just wanted to disguise himself and the belt was the only disguise on hand.
- One of the villains on Dynomutt, Dog Wonder assumed the disguise of an old woman so Dynomutt would help him escape in a taxicab. Blue Falcon wasn't so easily fooled.
- There are stories about Jesse James having done this.
- When Charles Stuart, the Young Pretender, was escaping from Scotland after the collapse of his rebellion, Flora MacDonald smuggled him onto a boat disguised as her maid.
- Male insurgents in the Middle East have been known to hide under burqas.
- As did a prime minister trying to escape during a coup in Iraq in the 1950s; he was caught because someone noticed that he was wearing men's shoes.
- William Wallace disguised himself as a woman more than once.
- Unfortunately a real tactic among suicide bombers, especially in countries where women wear concealing clothing, which makes disguising IEDs on their person much easier.
- Ehud Barak dressed in drag and pretended to be another soldiers girlfriend during Operation Springtime of Youth. The popular Israeli satire show Eretz Nehederet portrayed him once as going Ax-Crazy and demanding his dress to go fight at the slightest hint of an imminent armed conflict.