A 1970s horror film with incest between sisters. Eek.

Ellen (Lee Grant, Mulholland Dr., Dr T and the Women) and Cissy (Carol Kane, Even Cowgirls Get the Blues) are sisters who grew up in Africa with their father, a deceased primatologist. Cissy is more than a little crazy, and she lives in a room designed to be like Africa, with hot house plants, African artifacts and music, and a succession of apes and monkeys that she keeps in a cage.

Ellen takes care of Cissy, and their relationship is incestuous, as they sleep together and have sex in a hammock. Cissy is violent and kills her pet monkey, threatening to commit suicide if she can't have another. Ellen gets an orangutan for her after Cissy cuts her wrist, but that one is beaten to death as well.

When Ellen begins dating David (James Olson, Rachel, Rachel), Cissy can't handle it, and - surprise - she kills him as well, after chaining him in the monkey cage. Cissy now has Ellen to herself, chaining her in the cage until she dies.

It was torture for me to watch this really weird, uncomfortable horror flick. The film has actually made it to dvd and apparently has a cult following.