Jean-Marie Fayard is a young examining magistrate in a large provincial french city. He belongs to that generation of judges who are endeavoring to re-adapt the notion of justice to our changing times. His methods are not agreeable to every one. Criticism and pressure are brought to bear upon him but he is aware of his value, professionally, and refuses to make any concessions. He follows an unwavering course. He uses dynamic methods and takes uncustomary initiatives. He behaves like a crusader, a battler, whence the nickname given him by the reporters : the sheriff.

When political thugs murder an opponent's volunteer and also kill a cop, chief inspector Verjeat believes the politician who hired them is as guilty as the murderous goon. Verjeat's pursuit of the councilman, Lardatte, gets him a warning from his superiors. When he embarrasses Lardatte while disarming a hostage (the dead volunteer's father), Verjeat is told he's being transferred within a week. He speeds up his hunt for the goon and, with Lefévre, one of his young detectives, he engineers a complicated scheme to buy more time before the transfer. How should Verjeat play out his values of honor and duty?