Horror b movie about a scientist look for longevity
I'm not sure about from what decade this movie would be, but I would bet 60s. It is about a mad scientist, with some resemblance to Dr Jekyll and Dr Frankenstein. Searching the secret for longevity, he notices that women usually leave much more than men. In particular he observes the fact that seldom they get bald when older. He starts to kill women (I am not sure, but as I remember at the beginning he just collected dead bodies from cemetery). He got to a potion. The effect is that he turns into a woman. A creepy, but kind of mysterious and sexy woman. She has a long straight dark hair, and wears a long red dress, and is very cruel. She seduces men and then slays them. I don't remember the upshot.
