A psychiatrist joins forces with a prostitute to investigate the murder of a patient, a frustrated middle-aged housewife who indulged her fantasies by embarking on an extramarital affair and was subsequently killed. Brian De Palma's thriller, starring Michael Caine, Angie Dickinson, Nancy Allen, Keith Gordon and Dennis Franz.

After witnessing a mysterious woman brutally slay a homemaker, prostitute Liz Blake finds herself trapped in a dangerous situation. While the police thinks she is the murderer, the real killer is intent on silencing her only witness.