Florent Pagny

In the Belleville district of Paris, a police informant working undercover is murdered. As a result the police are anxious to find a new rat; soon enough they start working on Dédé Lafont, a smalltime gangster, and his girlfriend Nicole, a parisian hooker, in hopes that Dédé will be able to provide the cops the top mobster in Belleville, Roger Massina.

During a robbery gone wrong, Valentin Tralande kills his accomplices and bank customers. Only with a comfortable booty, loose ends, he tries to get to know a couple whose wife, Christine, is to his liking. (Wikipedia)