The uptight and slow-witted small-time thief Nick Robey and his partner and friend Al Molin rob a $10,000 payroll from a man, but the heist goes wrong as a policeman shows up. Al Molin is shot in the back by a policeman and Nick shoots the policeman. He hides out in a public swimming pool and meets the lonely spinster Peggy Dobbs in the water. Nick uses Peggy to lie low. He offers to escort her home and she invites him to her apartment, where she introduces her family to him. Nick decides to use Peggy's apartment as a hideout to wait for the police manhunt to cool down and takes her family hostage. The policeman dies, and Al reveals Nick's name to the police. When Nick finds that Peggy loves him, he invites her to leave town with him and asks her to buy a get away car. However, Nick cannot trust anybody and believes Peggy has betrayed him and becomes paranoid and panics.