 Ex-gangster Fernand (Lino Ventura) receives a call from a dying friend, a mob boss nicknamed "The Mexican". The doomed mobster talks Fernand into taking care of some criminal business and looking after his soon-to-be-married daughter. When a longtime mobster heavy, Volfoni 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.