Dirty Harry (1971)

Crime thriller directed by Don Segal. Clint Eastwood is at his best as the monosyllabic San Francisco cop who takes the law into his own hands to defeat a crazed murderer. 

The locations are perfectly chosen. Eastwood is effortlessly cool. The soundtrack by Lalo Schifrin is entirely suitable for the action but also works in its own right. The night scenes are atmospheric and suspenseful. And the psychopath Scorpio played by Andy Robinson is convincingly mad. 

Four sequels would follow.