In 1930 Marseilles two small-time crooks join forces when they meet brawling over a woman. Starting with fixed horse races and fights, they start to find themselves doing jobs for the local gangster bosses. When they decide to go into the business for themselves, their easy-going approach to crime starts to change.

Siffredi, a smalltime Marseilles gangster in the 1930's, is released from prison and searches for his former girl friend, Lola. He finds her with Capella, another gangster, and after they fight over Lola, the two men become friendly and decide to form a partnership. For a while they fix horseraces and prizefights until they are contacted by Rinaldi, a lawyer who works for Marello and Poli, the gangsters who control crime in Marseilles. Rinaldi suggests that Siffredi and Capella seize control of Marello's hold on the fish market business. They succeed in ousting Marello, but they are no longer content to remain in the background. In an attempt to gain control of Poli's meat market operations, Siffredi and Capella are nearly killed by Poli's henchmen, and they are forced to go into hiding. They emerge armed with machine guns and murder Poli. After Rinaldi is killed by "The Dancer," another aspiring gangster, Capella and Siffredi dispose of his body and establish themselves as the rulers of the Marseilles crime world. The two men become extremely wealthy, but Capella tells his partner that he is leaving Marseilles before they begin to fight with each other over control of their organization. As Capella departs, Siffredi sees him slain by a waiting assassin; Siffredi then realizes that his own position in Marseilles is tenuous and that he must leave.