The novel's protagonist is a school teacher named Theresa Dunn who is searching for the ideal man whom she names "Mr. Goodbar". Because of her nymphomania, she often visits bars and nightclubs late at night when she is unable to sleep, picking up random men. After she has sex with them, she makes them leave; she never lets a man spend an entire night with her. One night she is at a nightclub and meets a man that she likes. The two go to Theresa's apartment and have sex. When Theresa tells the man to leave, he brutally attacks and kills her. He considers himself her victim.