Don Siegel directs this thriller starring Clint Eastwood as Lieutenant Harry Callahan, a short-tempered San Francisco policeman willing to bend the rules to make arrests. The maniacal Scorpio Killer is on the loose and Callahan disregards procedure in his efforts to track him down, using his trusty Magnum .44 to dispense his own brand of justice. The cast also includes Harry Guardino, Reni Santoni and John Vernon.