Georges Lautner – Le Pacha AKA Pasha [+commentary] (1968)

Synopsis:
Early one morning, an armoured van loaded with diamonds sets out from the Place Vendôme in the heart of Paris to Bourget airport, accompanied by a police escort. Before it can reach its destination, the convoy is suddenly attacked by a gang of armed crooks, who show no mercy as they set about stealing the valuable cargo. The gang’s leader, Quinquin, has no intention of sharing his ill-gotten gains with his accomplices. As soon as he has taken receipt of the diamonds he begins eliminating all of his criminal associates, beginning with Gouvion, the police inspector who was charged with
delivering the jewels.

Police superintendent Joss is just a few months from a well-deserved retirement when he is tasked with investigating the jewel heist. Gouvion was a close personal friend of his, so his death comes as a shock and causes Joss to redouble his efforts to find the criminals. It isn’t long before Gouvion’s
part in the diamond theft is uncovered – it seems he was seduced by Nathalie, the sister of one of the crooks. Learning that her brother is one of the men who was killed by Quinquin in his purge, Nathalie agrees to help Joss bring the gang leader to justice, but she meets a nasty end when the gangster boss sees through her treachery.

Making full use of his informers and underworld contacts, the wily superintendent sets about laying a trap for his enemy by encouraging a rival gang to raid a postal train. Naturally these extreme measures bring him into conflict with his police superiors, but Joss is adamant that they are necessary to apprehend one of the most dangerous criminals in France. Quinquin swallows the bait and falls straight into Joss’s carefully laid trap. Once the train robbery has been carried off successfully, the two gangs confront each other in a disused factory and set about wiping each other out. Joss shows up at the end of this fierce showdown to deliver not justice, but a well-timed revenge…

— James Travers (frenchfilms.org)