While New York City architect Paul Kersey (Charles Bronson) is away from home, drug addicts break into his house and brutally murder his wife, Joanna (Hope Lange), and rape his daughter until she's comatose. Once wary of guns, Kersey takes matters into his own hands, seeking vigilante justice against not only the culprits, but other wrongdoers as well. New York City cops soon take notice and try to find the person who's doing their job.