Dr Jekyll And Sister Hyde
1971

For his research on finding the elixir of life, Dr Jekyll starts to use female hormones harvested from cadavers given to him by grave-robbers Burke and Hare. The serum has the unfortunate effect of not only changing his sex but also his personality. His alter-ego is gorgeous but evil.

In order to explain the appearance of a woman around the house, Dr Jekyll takes the identity of Mrs Hyde when he is in his transformed state.

Eventually Dr Jekyll falls in love with his upstairs tenant Susan Brodrick. To confuse matters, Mrs Hyde develops a desire for her brother. It leads to a struggle between their sexual identities.

To keep a regular supply of the serum, fresh female cadavers are required. This necessitates the killing of prostitutes which Mrs Hyde does with eagerness under the cover of Jack the Ripper. Dr Jekyll hates the killing, and there follows a struggle for dominance between the two personalities that could destroy them both.