Dr. Jekyll and Sister Hyde (1971)

Dr. Jekyll and Sister Hyde (1971) is a horror film, despite the punny title. Like the original material it mines, the setting is Victorian London, where Dr. Henry Jekyll, played by Ralph Bates, is experimenting with an elixir of life that is founded on female hormones, of course those hormones are extracted from freshly stolen female corpses. Naturally, the good doctor tries the potion on himself and is turned into a monster, a beautifully hot and sexy monster, played by Martine Beswick, but evil. Leave it to Hammer films to squeeze life from this tired franchise, and leave it to Martine to show us her tits twice and her ass once.