Rosemary's Baby is a 1968 American psychological horror film written and directed by Roman Polanski, based on the bestselling 1967 novel of the same name by Ira Levin. The cast features Mia Farrow, John Cassavetes, Ruth Gordon, Ralph Bellamy, Maurice Evans, Sidney Blackmer, and Charles Grodin. The film chronicles the story of a pregnant woman who deals with the problem of her body changing to carry an unknown baby.