Fashionable Manhattan therapist Dr Robert Elliott (Michael Caine) faces true horror when a psychotic killer begins attacking the women in his life (Angie Dickinson; Nancy Allen) with a straight razor stolen from his office. Desperate to find the murderer before anyone else is hurt, Elliott is drawn into a dark and disturbing world. And as the doctor edges closer to the terrible truth he is in danger of losing himself in a labyrinth of obsession, deviance and desire.