This crime comedy finds ex-gangster Fernand (Lino Ventura) receiving a call from a dying friend, a mob boss nicknamed "The Mexican" (Jacques Dumesnil). The doomed mobster talks Fernand into taking care of some criminal business and looking after his soon-to-be-married daughter (Sabine Sinjen). When a longtime mobster heavy, Volfoni (Bernard Blier) takes exception to Fernand for being an outsider, they come after Fernand who is equal to the task. He defends himself in a series of comical killings from the onslaught of the mob. Writer Albert Simonin adapted this comedy from his book Grisby or Not Grisby, with sharp dialogue written by Michel Audiard. Both Simonin and Audiard would later work on director Georges Lautner's Les Barbouzes/The Great Spy Chase which, along with Les Tontons Flingueurs, would again feature actors Francis Blanche, Lino Ventura and Bernard Blier.