After a frightening sexual attack by her father in law, Anna Forbes, a beautiful and successful ballerina, turns to her husband Mark for help. Convinced that the accusations against his father are caused by Anna's own fragile mental state, Mark takes her to a phychiatrist who puts her on a steady diet of prescription drugs that only escalate her terror. Soon, Anna is forced to fight for her very survival when Mark admits her into an instituition, and her real nightmare begins.....