1944: the Germans have opened a special POW camp for the prisoners who have a record of repeated escape attemps - Stalag Luft III. But as soon as they are settled in their new camp, British officer Bartlett and a hand-full of others begin to make plans for a large-scale breakout. Barlett intends to free 250 prisoners so that the Germans are forced to take soldiers away from other war duties. But first extensive preparations have to be made: three tunnels have to be dug, passports forged, civilian clothes made, etc. Eventually 76 prisoners manage to escape and scatter all over the country. Fifty are captured and then executed by the Gestapo. The rest is returned to the camp. Only three of them reach the border.