A pregnant woman is taken back to the house of her husband's mother. There she begins to have strange nightmare about her child and step-family. For the husband and mother are actually reincarnated lovers who were burned at the stake for practicing witchcraft. She must soon escape from their clutches or have her child sacrificed to Satan.When a storm strands a group on a Massachusetts island where the only dwelling is an old hotel supposedly haunted by the ghost of a former German actress (Knef), the result is the standard horror film as each of the cast is picked off one-by-one.