Dirty Harry novels of the four first "Dirty Harry" films as tie-ins. Author and screenwriter Phillip Rock wrote the novelization of "Dirty Harry" in 1971, based on an early draft of the script. Mel Valley wrote the sequel, "Magnum Force", in 1973. Wesley Morgan novelized "The Enforcer" in 1976. The "Sudden Impact" novelization was written by Joseph Stinson, one of the screenwriters. Stinson, who had rewritten the originally independent script as a "Dirty Harry" vehicle for Eastwood, adapted the novel in 1983. Following "The Enforcer", Eastwood announced that he would not make any further "Dirty Harry" films (he eventually returned to the role
Clint Eastwood in the 1970s presented with a script called "Moving Target" which had potential but needed a major rewrite. In the end it was decided to make a third "Dirty Harry" film. The script, devised by Stirling Silliphant had Harry up against a San Francisco Bay area Symbionese Liberation Army type group, which in real life had terrorized the area in 1974 with ruthless kidnappings and violence, and the film would end in a shoot out at the gang's hideout on Alcatraz island. Eastwood met Silliphant in a restaurant in Tiburon and instantly took a liking to the script, particularly the shoot out and