I think there was one before psycho. I saw it by accident late one night. It was a woman who became a man. She was raised as a boy in order to get an inheritance. In the movie she goes back and forth between genders. They don't let you know until the end, but I picked up on it early on.
Maybe it came after psycho, but I think it was a 50's thing.
actually, it was this one -
Quote12. William Castle's HOMICIDAL (1961) was the first post-Psycho rip-off. Castle shamelessly borrows the Hitchcock films prologue of the icy blond temptress on the run from the law. But here it is the blond temptress, played by Jean Arliss, who is the psycho, murdering anyone who comes between her and her horrible secret. Can you figure out that secret? Huh. I'll give you TWO guesses. While the secret may be utterly obvious to anyone with halfway decent eyesight Castle's film is totally enjoyable and quite spooky at times. Castle was a huckster but he was good at crafting a successful suspense scene. You should also check out his underrated spook-fest The Night Walker. No trannies in it but its scary as hell anyway.
