There is an impression that nudity in film is gratutitous there just to titilate, to get more viewers. This can be true, but nudity can be important to a film for a number of other reasons...
1. Realism
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| The Following |
People do actually get naked. Coy or clothed sex scenes and shower/bath scenes may be OK once in a while but too regularly they become obvious and self-parody.
2. Passion & Intimacy
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| You Only Live Twice |
Passion can be portrayed in clothed sex scene, but as with realism, too regularly and it loses its power, full nudity in a sex scene, however, remains a great symbol for passion.
Nudity during passionate sex is also a symbol for intimacy. Post-coital nudity or lack thereof also talks of intimacy. A night of passion, followed by coy nudity or overuse of bed sheets can effectively show that next-day regrets. However, if that is not the intent, then covering the nudity can send the wrong message.
For longer term relationships, nudity can show the intimacy of a long term couple. On the rare occasion it is shown as them being comfortable with each other, more often the lack of it shows the breakdown of a relationship. A film showing the life of a relationship will show them passionate and nude at the beginning, but lessen the nudity as time goes on (and the relationship becomes less passionate), or a film about an affair will show the married couple respectably dressed - even in bed - but the adulterous couple naked or scantly dressed together.
3. Naivety & Freedom
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| Sheena: Queen of the Jungle |
Uncivilised, native, etc, characters, foundlings, those raised in the wilderness, the Tarzan-type characters. Although, they often end up in loin cloths/furs (which make little sense) there are moments (usually bathing in streams or as children) of nudity to portray the innocence of the character. Aliens (especially shape changing aliens) or supernatural creatures can often initially appear nude to show their different cultural attitudes. The extreme example is Lifeforce where a energy-drain alien spends much of the film naked.
There are, of course, nudists or naturalists who believe that not wearing clothes makes them feel free. In A Shot in the Dark a nudist camp is shown but with strategic scenery. Being a slap-stick film that works, in more serious films it can seem camp. Other films, like Act Naturally, are less coy, showing copious amounts of nudity, but still remain coy about some nudity, meaning the characters didn't live up to the film title. Maslin Beach isn't shy or coy about the nudity on the beach of the same name, but the nudity becomes distracting and does nothing to hide the shallowness of the film.
4. Safety/Vulnerability
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| Psycho |
A lot is made of the horror film cliche is the frequent deaths of young females in showers. Yes, it happens, probably too often and mostly to cater to the audience. There is, however, thematic reasons for this. The shower scene usually when a character feels most safe, as shown by the fact that they feel safe to be nude. But it is because of this feeling safe which makes them the most vulnerable. A cliche becomes a cliche because it works.
5. Homage/Parody
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| The Adventures of Baron Munchausen |
There are a lot of homage/parody films out there, increasingly for the Slasher genre. Two such films are Scream (1996) and Cabin in the Woods (2012). Scream was noted for its subversion of Slasher rules but having Sidney flash, and later have sex with her boyfriend. However, since it was done coyly or off-screen, it followed the slasher trope of having the final girl covered and nude/having sex off-screen. Cabin in the Woods meanwhile commented on-screen about the nudity equals death trope, but did receive criticism backing it up with actual nudity.
6. Humiliation/Dehumanisation
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| Salo |
Nudity can be used to portray the humiliation of a character. St Trinians, for example, included a scene where "the new girl" was tricked into running naked through the school. In Blue Velvet, a beaten and bloody character stumbles naked into a group of people looking for help. The level of nudity can change the mood of the scene: St Trinians scene was played for laugh and nothing was shown; the Blue Velvet scene included full frontal nudity and felt truly humiliating. If trying to show the humilation is the point of the scene, coy nudity can undermine it, whilst more complete nudity can make the viewer feel a party to the humiliation and undermine the laughs. There are always exceptions and Jason Segeal's full frontal nudity in Forgetting Sarah Marshall is comedic and portrays humiliation.
More extreme than humiliation is dehumanisation. The nudity of corpse (both found and in the morgue) is, of course, the most dehumanised a person can be. However, there are other situations, such as portrayal of mass nudity in concentration camps in films like Schindler's List.
7. Voyeurism
Not the audience, the character's voyeurism. Whether it's the "fun" voyeurism of young men violating the object of his desire's privacy (such as the shower scene in Porky's or the hidden cameras in Revenge of the Nerds) or the creepy voyeurism of a stalker or killer (Psycho, for example) if the audience doesn't see what the voyeur sees it becomes ambiguous. Of course, as with humiliation, the more you see with creepy voyeurism, the creepier it can feel for the viewer. And the more you see with "fun" voyeurism, the more it's about titillation and makes the misogynistic act seem legitimate behaviour. Female voyeurism on males is less likey to be see as misandry.
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| National Lampoon's Animal House |
Not the audience, the character's voyeurism. Whether it's the "fun" voyeurism of young men violating the object of his desire's privacy (such as the shower scene in Porky's or the hidden cameras in Revenge of the Nerds) or the creepy voyeurism of a stalker or killer (Psycho, for example) if the audience doesn't see what the voyeur sees it becomes ambiguous. Of course, as with humiliation, the more you see with creepy voyeurism, the creepier it can feel for the viewer. And the more you see with "fun" voyeurism, the more it's about titillation and makes the misogynistic act seem legitimate behaviour. Female voyeurism on males is less likey to be see as misandry.
8. Misogyny/Misandry
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| Action |
While female nudity is often described as misogynistic, and is often is, it can also be used show a charactger (usually a villains) misogyny. Strip clubs, nude or semi-nude woman in a criminal's mansion, or a serial killer's victims being naked. Male nudity can even be used to show misgynistic behaviour if the character uses their nudity as a form of intimidation.
9. Intimidation
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| Sherlock Holmes: Game of Shadows |
A character can be naked to intimidate another character, for example the nudity of Irene Adler in both recent Sherlock Holmes film and the Sherlock TV series, to sexually intimidate the title character, or in the TV series Action where Bobby G used it to intimidate Peter Dragon.
10. Decadence/Self-Indulgence
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| Caligula |
Nudity, especially large amounts of nudity of both sexes can show decadence or a society/groups self-indulgence, especially in orgy or swinger scenes. The more nudity, the stronger the symbolism. A bunch of people in their underwear or a nude girl in a group of people doesn't have send the same message as a large group of unclothed people in a similar situation. Whether the scene is for or against such decadence depends, of course, on the film.
Gratuitous Titillation
No matter what the underlying message, almost all nudity will be seen by someone as gratuitous titillation and some is nothing but. And just many of the above categories have crossover, titillation can crossover with "legitimate" reasons for nudity: even the most justified nudity can also be in there for titillation. And even there will be people titillated by anything.
