Dirty Harry local and federal police committing offences and overstepping their authority by entrapment and obstruction of justice. Author McGilligan, argued that America needed a hero, a winner at a time when the authorities were losing the battle against crime. The box-office success of "Dirty Harry" led to the production of four sequels. In the 2007 film "Zodiac", also set in San Francisco and inspired by the Zodiac Killer, cartoonist Robert Graysmith approaches police detective Dave Toschi at the cinema, where he is watching "Dirty Harry" with his wife. When Graysmith tells Toschi he is going to catch the Zodiac killer, Toschi
Dirty Harry (character) wife that his wife was killed by a drunk driver. She appears in "Magnum Force" in an old photograph which Harry turns around. The doctor tending to him after the first film's bank robbery intimates that "us Potrero Hill boys gotta stick together". The first film's novelization explains that Callahan grew up in this neighborhood and describes a hostile relationship between the police and the residents. Callahan recalls once throwing a brick at a police officer, who picked it up and threw it back. The following sequels show that Harry lives within the city limits in a small studio apartment