A group of French soldiers, including the patrician Captain de Boeldieu and the working-class Lieutenant Maréchal, grapple with their own class differences after being captured and held in a World War I German prison camp. When the men are transferred to a high-security fortress, they must concoct a plan to escape beneath the watchful eye of aristocratic German officer von Rauffenstein, who has formed an unexpected bond with de Boeldieu.

The early days of the French Revolution, as seen through the eyes of the ordinary citizens in Marseille and the royal court, including King Louis XVI and Marie Antoinette.