It's a Xmas 1944 for the American POWs in Stalag 17. For the men in Barracks 4, all sergeants, have to deal with a problem - . The Germans appear to be forewarned about escapes and in the most recent attempt the 2 men, Manfredi and Johnson, walked into a snare and were killed. For many in Barracks 4, especially the loud mouthed Duke, the leaker is obvious: J.J. Sefton, a wheeler-dealer who doesn't hesitate to deal with the guards and also who's acquired goods and privileges that no other prisoner seems to possess. Sefton simplifies providing the Germans any advice and makes it quite apparent he does not have any intention of trying to flee. He intends to ride the war out in what comfort they is able to arrange, however it doesn't extend to spying for the Germans.