Three female college students, Terry, Nancy and Gloria, embark for a music festival in rural Washington. A sudden storm causes Nancy to accidentally crash the car, rendering all three unconscious. Terry awakes to find her and her friends alive, sheltered in a large mansion in the middle of nowhere, owned by the Penroses: the middle-aged Marion, her mother, and their groundskeeper, Norman. Gloria is the only one with serious injuries, so Marion suggests that they spend the night until Gloria is able to leave. Terry and Nancy are invited to dinner with Marion and her embittered and elderly crippled mother. Throughout dinner, Marion's mother rants and raves about her disgust toward men, and how her husband left her for another woman. She also recurrently accuses Marion of bringing men into the home. Later, in a music room, a mysterious man looks menacingly into the windows at the women.