June 1944, a French town towards the end of the occupation. Following several attacks perpetrated by the resistance, the inhabitants who listen to English radio are rounded up by the Germans in a prison and considered as hostages. In one of the cells are found men from all walks of life: an aristocrat, the Viscount of Saint-Leu, Doctor Noblet, a resistance fighter, Béquille the wanderer with a wooden leg, and a strange character nicknamed "Black Market". The latter arouses mistrust among the prisoners, because it could well have been introduced by the enemy.