Compressed Hair

Let's face it. Hair that is striking in its length, volume, or color makes a very dynamic visual, and as such, many a work of fiction will have a character who has it. But wait! For some reason or other, the person with the striking hair needs to be disguised so that either other characters, the audience, or both don't realize it's them.

The easiest way to do this is to conceal their hair under a helmet, a wig, or with a hat, cap or scarf. This also gives the author the potential to toss out The Reveal with a dramatic explosion of flowing locks as the character's most prominent attribute positively identifies them for all to see.

Except...hair doesn't entirely work that way. It can range from "fairly difficult" to "really freakin' hard" to successfully compact and store long or thick hair in such a small space. And even if it can fit, there's a real-life phenomenon known as "helmet hair" -- hair that's been tucked up under a close-fitting piece of headgear for very long tends to be not so flowing and perfectly styled when it's released.

If The Reveal is particularly huge or unwieldy, it may result in Please Keep Your Hat On.

Anime and Manga

 * Revolutionary Girl Utena The Movie had Juri and Utena's character designs altered significantly. While Juri's hair has always been insanely elaborate, the volume of hair she fits in a simple fencing helmet (full French curls plus Rapunzel Hair that extends almost to her knees) is just ridiculous. Utena, by contrast, actually has character sketches that show how her relatively more modest length of hair could in fact be braided tightly enough to manage hiding it under her hat. Of course, when she takes her hat off it's not braided at all...
 * Even bigger than either of them is Anthy in the television series and the manga. Normally it's curled above her neck; when the third story arc begins, the viewers are shown that it's actually long, flowing, wavy hair, and it symbolizes her true self. In the movie, it's always down and flowing.
 * From Eroica With Love subverts this, actually, where Dorian's insanely long curls have to be cut so he can wear a wig and disguise himself for some good old-fashioned negotiation. Surprisingly, they take a realistic amount of time to grow back, as well.
 * C.C. of Code Geass does this almost any time that she impersonates Zero by wearing his outfit. Her waist-length hair just magically manages to fit into the Zero mask. Oddly averted later when everyone is wearing Zero costumes in R2, and C.C. has her green hair notably extending outside of the Zero mask in a way that'd easily identify her if not for the I Am Spartacus moment.
 * Averted in Elfen Lied. Lucy's helmet when she's in the lab is longer on the back, providing enough space to fit her hair, which goes past her waist.
 * Juliet of Romeo X Juliet could conceivably hide all her hair under her wig if she twisted and pinned it, but when she simply removes the wig and lets the long hair fall it's perfect and unbound. How she got it all up loose is anyone's guess, how it was let down unmussed is a small miracle.
 * Taiga from Toradora has fairly long, poofy hair, but manages to get it done up in two small buns when she goes swimming.
 * How on Earth Planet Solo does Cosmo Yuki manage to make his Funny Afro fit inside his helmet?
 * In Halo Legends, manages to fit a surprising amount of hair into her helmet to make The Reveal more dramatic. It's also not shown to be bound in any way so it can flow dramatically. From the same series of shorts the Spartan Daisy is shown with a much more realistic Bob Haircut that would be able to fit into her helmet.
 * Alto of Macross Frontier fits a high ponytail into his close fitting helmet. Either he has a special helmet with a hole cut for his hair or it's magic
 * In Gundam 00, Princess Marina Ismail is guilty of this when she goes on a world tour to negotiate a solar power generation system. How she keeps her butt-length hair rolled-up is anyone's guess.
 * Soma Peries also has this problem, but it's averted as the helmet on her customised pilot suit has a visibly larger helmet than the male pilots.
 * Washu from Tenchi Muyo seems to be a master at this given various scenes.
 * Though considering she can use the power of SCIENCE to alter her very age at will, compacting her massive pony tail is hardly impressive.
 * In Ronin Warriors, sometimes we see Seiji's hair maintain shape whilst meditating in a waterfall, yet it will fit in a helmet much smaller than his 'do.
 * Inverted in Saint Seiya. While Andromeda Shun's normal hair length barely goes below his shoulder line, wearing his helmet causes it to basically become Rapunzel Hair.
 * In Kuragehime, while giving the Sisterhood makeovers, Kuranosuke is unable to straighten Banba's Funny Afro, so he plops a wig onto of it instead, somehow managing to keep all of her hair inside it.
 * In Pokémon Special, Yellow hides her ponytail under her hat to pretend to be a boy.
 * In Fushigi Yuugi, Hotohori, when conducting emperial duties, often tucks his beautiful, long locks up into the tiniest bun on the top of his head.
 * Sieglinde Jeremiah of Magical Girl Lyrical Nanoha Vi Vid, who manages to keep the entirety of her long, thick, Girlish Pigtails under the hood of her coat.
 * In Yu-Gi-Oh, when Mokuba challenges Yugi during the Duelist Kingdom arc, he's wearing a disguise in which he manages to cram his three pounds or so of hair underneath a cap.
 * Hanaukyo Maid Tai. Cynthia keeps her hair loose, but on the very same head under the very same cap Grace keeps the very same hair, without changing the volume of the cap itself.

Comic Books

 * Depending on who's drawing him at the time, Wolverine's flared mask could concievably contain his distinctively flared hairstyle (they're rarely drawn to actually match up, flaring-wise - in fact, the haircut came a while after the mask; he's never unmasked in his first appearances). The muttonchop sideburns are a different matter - some artists don't even bother to draw his mask covering the parts of his jaw where there's hair when he's unmasked. And how does his hair stay so distinctively flared when he keeps wearing a mask over it?

Fanfiction

 * In Kyon Big Damn Hero, Tsuruya begins their first Curb Stomp Battle by revealing her identity. She pulls off a blonde wig, and her ankle-long green hair drops to the ground. This is soon followed by Kyon and Yuki shifting into martial arts mode, and beating all 24 of their opponents into a lengthy stay at the hospital.

Film

 * Averted in Victor Victoria, in that Julie Andrews has her hair cut that short to perfect her Count Grazinski look. Double averted in that the "drag reveal" involves a woman pulling off a long wig to reveal short, mannish hair.
 * Anya in Anastasia Appears to have a small ponytail for most of the movie, but when she lets her hair down later when she's all dressed up, her hair is much longer than the ponytail would account for. If you look closely, at the small "ponytail", though, you can see that it's actually only the ends of her hair sticking out of a very tight bun.
 * In She's the Man Viola impersonated her brother in order to get into a boys football team. She hides her hair under a boy-wig, which she removes in the movie's climax football match. Seeing the length, it makes one wonder.
 * Danielle in The Flight of Dragons has one of these moments during her Samus Is a Girl reveal, taking off her Robin Hood cap to reveal a cascade of long red hair.
 * In Shakespeare in Love, Gwyneth Paltrow managed to get her waist-length hair under a short wig so she could disguise herself as a teenage boy and thus play the part of Romeo, in which she let her real hair down.
 * In Disney/Pixar's Up, young Ellie takes off her flying helmet to reveal a bushy head of hair, made to look bigger by "helmet hair" and static electricity.
 * In The Princess and The Frog, Facilier's hair is about the same height as the hat he's trying to keep it under.
 * Rapunzel in Tangled uses this as character development - when she enters the kingdom for the first time, the long hair she had to keep for Mother Gothel's sake is immediately an encumbrance to her joining in the festivities and Flynn recruits a group of young girls to braid it until it's compact enough to be off the ground.
 * In Cannibal the Musical Matt Stone's character has a huge afro underneath his beaver hat.
 * The evil Queen from Snow White and The Seven Dwarfs. This is most noticable during the scene where she turns into the Witch.
 * In the Star Wars franchise, Leia's hair is much longer than her iconic cinnamon buns would suggest.
 * Brenda fitting her hair into that hoodie in Urban Legend.

Literature

 * In the X Wing Series of the Star Wars Expanded Universe, there are a number of Twi'lek pilots. No mention is made of how they accommodate their brain-tails to their pilot helmets, though there are apparently "socks". But on at least one occasion, they dress up in stormtrooper armor, and the Twi'lek character is specifically commented on as probably being very uncomfortable with her sensitive brain-tails all scrunched up in the helmet.
 * The Lord of the Rings plays this straight when Eowyn removes her helmet at the climax of a pitched battle. Interestingly, though, The History of Middle Earth has revealed that in an early draft of Return of the King, Tolkien averted the trope instead--originally Eowyn cut her hair short before donning men's armor.
 * The children's novel Half-Magic has Katherine whipping off her helmet after defeating one of King Arthur's knights, with her long brown hair revealing that she is a female . . . and also nine years old.

Live-Action TV

 * Shepherd Book from Firefly has a rather scary version of this trope.
 * Jeri Ryan's hair is mid-back length, but she wore it tightly braided to play Seven of Nine on Star Trek Voyager.
 * Inverted with the 60s Batgirl, whose long red hair was actually a wig to help further conceal the fact that she was secretly Barbara Gordon with the short black pixie-cut.
 * This is also how the modern Batwoman conceals her identity, hiding her short red hair under a long red wig.

Music
"And the sign said "Long-haired freaky people need not apply"
 * The song "Signs" by Five Man Electrical Band has these lyrics:

So I tucked my hair up under my hat and I went in to ask him why

He said "You look like a fine upstanding young man, I think you'll do"

So I took off my hat, I said "Imagine that. Huh! Me workin' for you!""


 * Also shows up in the Charlie Daniels song "Uneasy Rider." The narrator gets a flat tire while driving through Mississippi and has to stop at a redneck bar so he can call for repairs. He stuffs his long hair into his hat, trying to hide his counterculture leanings, but eventually has to take it off. The locals are not amused.

Theater

 * Not universal, but very common in Twelfth Night and the rest of Shakespeare's comedies of crossdressing. Why did no one ask Cesario why he never took his hat off for three months?

Video Games

 * Millia Rage (Guilty Gear) is probably the most extreme example of this trope. Her hair naturally falls to her ankles while tied up, but she also uses it as a weapon, and it takes huge and ridiculous shapes. Also, in one winning pose, she takes off her ponytail and her hair flops to the ground, stretching to about two feet from her!
 * In-universe, explained by it not being hair but a magical symbiote permanently bonded to her which has a high-end Healing Factor. How it retracts again, though...
 * Noel Vermillion's (Blaz Blue) long hair is usually kept up in a beret, somehow.
 * Samus from Metroid certainly qualifies. This may be a reason they cut her hair in Other M.
 * Between the Morph Ball mode and her 200+ missiles, keeping a ponytail underneath her helmet is a minor trick.
 * Multiple members of Organization XIII in the Kingdom Hearts defy the laws of physics by managing to keep their Anime Hair hidden under their hoods. Vanitas hides in a perfectly head-sized helmet, which is partially explainable by the fact that he doesn't so much as remove his helmet as transform it Also, Zack Fair can hide his big spiky hair under a Spartan style helmet. Ventus is a borderline example. Then there's Terra, who somehow crams all of his thick hair (which reaches to around his shoulders) inside his head-sized helmet. Though for Ven and Terra, the helmets are summoned on.
 * Cecil Harvey has a mane of long, flowing white hair under his Dark Knight helmet. Golbez also has long white hair under his horned helmet. Averted with Kain Highwind whose Dragoon mask has room in the back for his blonde ponytail.
 * Edea of Final Fantasy VIII in her first scene, where her long hair just disappears inside her headgear.
 * Ron Delite of Ace Attorney fame has hair that resembles cinnamon buns. Fans often wonder how it could possibly fit in.
 * Custom character creation and Clothing Damage in Soul Calibur IV combine to allow this. You can give a character a huge afro and put a close-fitting helmet over it, and it'll magically be sucked into hammerspace. Until you break the helmet in combat, that is, at which point it erupts. Players have been known to lose matches from the distraction.
 * from Okami somehow keeps his ankle-length locks completely hidden beneath his hat/helmet, which perches jauntily on the top of his head.
 * In World of Warcraft whenever players put on a helmet all of their hair disappears under it. The same applies if they put on a hat, even if their hair is three feet long and they're wearing a small cap.
 * Grand Theft Auto San Andreas. The player can choose to get a giant afro, which remains entirely undamaged by the wearing and removal of any headgear.
 * Dissidia 012 Final Fantasy shows that the Warrior of Light is hiding incredibly spikey, fluffy hair under his helm.
 * Sougetsu Kazama (Samurai Shodown) besides using water ninjutsu, must know some of hair ninjutsu, since to make a column of water rise, his hair unties by itself as he turns gracefully. In one of his victory poses he actually unties his hair with one hand, and it just flows and flows until it actually reaches the floor! Amazing that he never used it to attack...
 * The Legend of Heroes VI Tita Russell.

Webcomics

 * Nightfall in Elf Quest. She wears a headscarf most of the time, except when she's literally letting her hair down.
 * Cuanta Vida: How the heck does Jordi/Bleu/BLU Spy fit his poofy, scruffy hairstyle into his class's tight-fitting balaclava without making it look all lumpy? Early on it's fairly believable, but his hair gets pretty long as the comic progresses.
 * In Dominic Deegan, Pamela's nurse cap is pretty small, but when she takes it off . ..
 * Collar 6: When Sixx's hair is in a pony-tail it reaches to her knees., also has this, having hidden her long, wavy black hair under a shorter blond wig.
 * Homestuck: Vriska Serket and Aradia Megido both have very long and unkempt hair. How they fit it all into is anyone's guess. In a lesser case, Nepeta Leijon's hair is taller and wider than the tiny cat cap she normally wears.

Web Original

 * Spots the Space Marine has thick dark hair that comes down to her ass, yet she can tape it up so it fits under her helmet.
 * In this picture, take a look at what Jasmine and Aurora have on their heads. It's like most of their hair is gone.
 * Cub from Happy Tree Friends has long, messy red hair hidden under his small hat.

Western Animation

 * As shown in the image, Eowyn in the Rankin/Bass adaptation of The Return of the King.
 * When not wearing his green cap, Kyle Broflovski sports a huge "Jewfro" that's like twice the size of the hat that hid it. Afros and other curly hairstyles compress quite a bit, since much of the volume is down to the shape of the hair rather than its mass.
 * Similarly, in an episode of Duckman, Cornfed pulls off his rather small hat and an enormous afro-like hairdo comes ballooning into view.
 * Avatar: The Last Airbender just loves this trope. Zuko's Season Three shaggy emo boy mop can be tied neatly into a topknot; Katara's slim braid disguises hair so thick it is wider than her shoulders (which is actually realistic as her hair is showing to be wavy, and thus really can compress like that); Azula's little topknot/hair antennae combo, when let down, reveals waist-length locks; and in a reversal, Sokka's ponytail implies hair about shoulder-length, but when untied is barely level with his chin, and it's in a sort of wedge cut that would really be impossible to get into any semblance of a ponytail.
 * It's not a ponytail, it's a warrior's wolf tail!
 * Marge Simpson occasionally manages to fit her enormous beehive under incredibly small hats.
 * Comic Book Guy gets a bit of this in an episode as well. When Bart is haggling with him over trades, he offers to throw in his "man-scrunchie". Tied back, his hair seems to be your typical balding-guy ponytail. But once unleashed, it flows with volume and sheen worthy of Salon commercial.
 * It takes no time for Kim Possible to fit her waist-length hair under a helmet, even if it's automatically popped on her head by a gadget.
 * Shego's hairdo, on the other hand, outright shrinks by 50% the only time we see her out of costume.
 * There was one episode of Danny Phantom that had Sam donning a Gothic-like wedding gown. Her usual short hair suddenly seem to grow twice its size when styled into two wild ponytails. Rapunzel Hair Jazz once squeezed her entire hair inside the Fenton hazmat suit she was wearing.
 * Despite having gravity-defying hair several feet tall, Teenage Mutant Ninja Turtles: Fast Forward villain Jammerhead is able to hide it all under his cloak without any trouble.
 * One episode of King of the Hill had Dale telling a story of his version of events. In the story, his characteristic hat falls off revealing, not his usual bald head, but what can only be described as a glorious mane of flowing hair.
 * Ten from Batman Beyond has a rather voluminous head of blond hair, but in costume her head is as smooth as an egg.
 * The futuristic Animated Adaptation of the French character Fantomette has her hide long black hair under a redhead wig no larger than a helmet.
 * As part of her Samus Is a Girl reveal in The Flight of Dragons, Danielle initially appears wearing a Robin Hood style cap, then removes it to reveal her long, flowing red hair.
 * Roger of The Life and Times of Juniper Lee is almost always seen wearing a blue beanie cap. When forced to take it off for picture day, he is revealed to have a truly epic afro. How epic? He needs help to get the hat back on.
 * Finn of Adventure Time has a hat that holds a mane of blond hair bigger than himself.
 * Given a humorous twist in The Venture Brothers. A flashback to when the Monarch was just starting off as a villain revealed he used to wear a helmet instead of his crown/cowl look. The helmet wound up giving him compressed eyebrows, which poofed out when he took it off.
 * In the Futurama episode "Xmas Story", in a scene parodying The Gift of the Magi, Zoidberg, Amy (whose hair could easily lend itself to this trope), and Hermes are all wearing hats. Zoidberg offers Amy a set of combs, only for her to take off her hat and reveal she sold her hair to a wigmaker so she could buy a set of combs for Hermes. "Oh, the irony," says Hermes, who also reveals he sold his hair to buy a third set of combs for Zoidberg. Zoidberg thanks Hermes for the combs, then takes off his hat to show he now has Amy and Hermes's hair, exclaiming "Finally, I look as pretty as I feel!"
 * My Little Pony Friendship Is Magic has Pinkie Pie's chicken costume in the episode "Luna Eclipsed," which makes her seem bald. Her ears are compressed, as well; her head seems completely round.
 * In An Extremely Goofy Movie, Goofy makes his 70s-esque entrance into college by removing a hat, revealing a large afro (actually a wig).

Real Life

 * Depending on how long someone's hair is, wrapping it up in a towel after washing it can have this effect.
 * This hairstyle.
 * There is a Speedo long hair swim cap out there, sold on Amazon.com. Given that whoever is seeking to buy this wants to actually fit all their hair in that swim cap and for said cap to actually fulfill its purpose, that swim cap most likely fits this trope.
 * Even a regular Speedo silicone swim cap will accommodate over two feet of straight hair of average thickness, if it's braided and coiled.
 * Just braiding hair that's long enough to be braided can compress it to a small degree. However, as the number of strands in the braid goes up, so does the amount of compression of the hair that is braided. Braiding is especially good for achieving Compressed Hair if the hair is braided tightly, like Jeri Ryan did to act in Star Trek Voyager
 * Any Sikh man wearing a turban. All Sikhs are required by religious obligation to abstain from cutting any of the hair on their bodies, ever. This requirement results in impressive lengths of hair. Since Sikh men are required to wear turbans, they are putting hair at least two feet long into that turban.
 * Some marching band uniforms require girls with hair past their shoulders to tie it back and shove it all inside their hats somehow.
 * Some people with long hair (usually women and girls) who wear their hair up and then let it down will sometimes get comments from people who are surprised to learn just how long their hair actually is now that it's down.
 * If your hair is straight, it may be surprisingly compressable, even if it's long. A lot of period hairstyles (and, famously, Princess Leia's double-buns) actually require extra padding or hairpieces, or sometimes backcombing and a lot of hairspray, to produce the volume of hair required.
 * Phoenix Jones was hiding a hi-top fade under his superhero mask.
 * Anyone who's ever worked in theater and was required to wear a wig has developed some impressive tricks to hiding their hair. Between pins, braids, coils, and caps, it's possible to hide quite a bit of hair under a wig. Watch this video through to the end to see how much hair Kristin Chenoweth hid under her Sally Brown wig.