Le Doulos (1963)

Synopsis
Confusion and wrong assumptions are the cause of tragedy in this stylish gangster noir by director Jean-Pierre Melville. Maurice (Serge Reggiani) and Silien (Jean-Paul Belmondo) are friends going way back, and both have had a shady past. Silien wants to leave his illegal activities behind him -- but would he actually be in league with the police, as an informer? That is what Maurice suspects after he kills a fence who is responsible for the murder of one of his friends and then takes some jewels as an extra bonus. Doubts assail Maurice as well as others until it is finally decided that something has to be done about Silien. ~ Eleanor Mannikka, All Movie Guide