France, 1940. During the exodus, Captain Cousin, a writer obsessed with dreams of glory, earns the admiration of Corporal Morvan, whom he meets along the way. Together with Claire Morvan, Morvan’s sister, they are filled with enthusiasm and decide to take action by making their way to England. They join the Resistance and are sent back to France on a mission that goes awry. Arrested by the Gestapo, Cousin gives them up, unlike Morvan. But to hide his cowardice from the others, he makes it seem as though Morvan was the one who betrayed them, erasing all the evidence except for one piece.