At 35, Toni Veronese (Daniel Duval) is a cruel and rigorous gangster. For a rigged boxing match, he fined (5 million francs) a manager protected by the powerful Perez brothers. When they refused, Veronese attacked the Perez properties, which he blew up nightclubs and brothels. Disarmed, Commissioner Claude Joinville (François Périer) called on Antoine Bini (Julien Guiomar), a justice-of-the-peace gangster, to put an end to this war. Bini condemns the Pérez to pay and they bow before the "judgment". But, when receiving the money, Véronese shoots two bikers from the police and one of the Perez brothers. Resolved to take revenge, the Perez hire a killer to execute Toni Véronese but it is the latter, alerted by Maria, his mistress who kills the killer. Bini then decides to intervene energetically to eliminate the gangster who has become too bulky and he in turn hires Paul Franchi, known as Bébé, and his gang of young thugs. These lure Véronese's gang into a trap and shoot on sight.