The successful and well-to-do architect Paul Kersey lives with his family in New York. During a robbery in her apartment, Kersey's wife is killed by juvenile criminals. His daughter survives the brutal crime, but has suffered a severe, incurable trauma and is admitted to a mental hospital completely apathetic. In view of the helplessness of the police in solving the case, the desire for revenge grows in the die-hard pacifist. When he himself becomes the victim of a robbery one day, he uses his weapon in self-defense - a key experience for him: As a self-proclaimed avenger, Kersey takes action against New York's criminals from that moment on and kills anyone who gets in front of his gun. Within a short time, the crime rate actually decreases and the unknown 'vigilante' is celebrated as a hero by the media and citizens. One day, however, the police find out about Kersey ...