Karl Lippert has two problems, on the lam after a robbery that resulted in murder, he's brought his wife with him, and the police are trying to locate her because she is taking medicine that has accidentally been switched with a deadly poison.
Key men at an electronics firm are being murdered, but no motive can be discerned. Lt. Adams enlists the help of psychiatrist Buel Reed, who explains the killer may actually want to be caught, and can be, if only the clues present can be understood.
At an old folks home, a woman working undercover for the police is murdered, and the owners of the home are the prime suspects, as they have scammed their residents in the past. When they try to run away, it seems all but certain they're guilty, but Adams believes the killer is one of the home's residents.
The Metropolitan Squad pursues a man who killed a housewife. The killer tricked the housewife to letting him in her house, making her believe he was a friend of her husband. The killer selects his victims after picking up information from people who have given a ride while he hitchhikes. Now, a woman who was assaulted by the killer earlier comes forward as new clues emerge about his M.O. Adams and his men race to find the killer before he can strike again.