The blockhouse (1973)

A group of Slave workers, drafted by the Nazis to help construct their coastal defences in 1944, are trapped in an underground bunker when the Allies land at Normandy on D-Day. They find huge stores of food, but not enough candles. The slow dying of the light parallels their increasing boredom, illness, and jealousy during their entrapment. Based on the Novel 'Le Blockhaus' by Jean Paul Clebert