Set in the East of France during the First World War, in a village close to the front which has been drained of its males because of the war, three powerful men have remained behind: the elderly Prosecutor-General Destinat, the scheming judge Mierck and the pussilanimous local police officer. They are confronted with the violent death of an innocent young girl named Belle; all three in their respective functions need to solve the mystery of who has killed her and why. But what is the sense in solving the mystery of this one death by crime if just outside the village there is a battlefield where thousands of men are killing one another? What made Belle's life more valuable than the lives of those who died on the same day at a short distance?