In a small town in France, Louis lives in a large tumbledown house where he looks after his disabled and eccentric mother and works by day as the postman.

Henriette, the post office clerk, keeps trying to inveigle him, but he spends his evenings tending to mis mother's demands and spying on his three enemies: the lawyer Lavoisier, the doctor Morasseau, and the butcher Filiol, three leading citizens who have formed a syndicate to buy and develop Louis' house.

Not averse to beating and waterboarding suspects, he finds that the situation is considerably more complex than it originally seemed: the lawyer Lavoisier has a mistress, Anna, who is friendly with the doctor Morasseau's wife, Delphine, but women vanish in quick succession.

Jonathan Rosenbaum in the Chicago Reader said that the film "wasn't a masterpiece, but at the very least it was a well-crafted and satisfying entertainment", and that it had "sex, violence, dark wit, a superb sense of both the corruption and meanness of life in the French provinces, a good whodunit plot, Balzacian characters... and very nice camera work by Jean Rabier.

"[4] Variety said "the plotting here wouldn’t pass muster on an episode of PBS’ “Mystery!,” but there’s pleasure to be had in veteran thesp Jean Poiret’s soaked-in-vinegar turn as Lavardin, a gimlet-eyed sleuth with a violent streak that surfaces unexpectedly, yet always at just the right moments.