A detective is assigned to track down and capture a crazed serial rapist.

Hess is a serial rapist at large in Los Angeles; his modus operandi is to gain entry into the home of a married woman whose husband is away, by pretending to be there to repay money the husband loaned him. Once inside, he feigns a headache, pulls out a tin of aspirin, and asks the woman for water. While she is distracted by this errand, he sneaks up behind her, then assaults and rapes her. He leaves the tin of aspirin behind as his calling card, leading the police to call him "The Aspirin Kid." Leaving the scene of the first assault portrayed in the film, he is nearly hit by a car. The driver, a police detective named Culloran (Steve Cochran), gives him a lift, and the two engage in conversation. The rapist calls himself Arthur Garret, and as the two talk, he learns that Culloran is married, and sees his address on an envelope on the car seat. After getting out of Culloran's car, he writes down the name and address, and the word "married," foreshadowing his later rape of Culloran's wife.—Watch_Movies