Behind the Nudist Curtain (also known as Nature. Girls. Unlimited) is an American 1964 nudist film produced and directed by Doris Wishman and starring Sandra Sinclair. The New York Times lists it as one of the "berserk sexploitation pictures" made by Wishman.
The film is now considered lost.
The film was "built out of scenes from a European travelogue, into which Wishman spliced the requisite nudist footage". It was WishmanâÂÂs last nudist film.