My favourite Wilder movie. I think it's fabulous - funny, exciting, tells a good story. Has aged very well. Cynical tales often do. It's not without sentiment - a pause when some mail comes through for one of the soldiers who was killed at the beginning. It also touches on some very big issues in a subtle way - Harry making a joke about them being turned into lampshades.
As typical for Wilder, the characters are very vivid - everyone remembers Sefton, the wheeler dealer, but it's not an out and out star vehicle, as befits it's Broadway origins; supporting characters make an impression too: Schultz, noway near as buffoonish as he was in Hogan's Heroes (he pretends to be but here he's also smart when the Americans aren't around); Price, the traitor; Hoffy, the leader, hot headed Duke; the comedy team of Animal and Harry; than random Bagradian character who is there to give Dunbar exposition - so to liven him up they make him good at impressions! (I think this is an example of what Blake Snyder calls "the Pope in the pool").
Most of all there's Joey, a character I never thought of much but who really hits home now - someone so traumatised by war he's basically an idiot. There's not much to Cookie and Dunbar is a brave aristocrat.
Much of this is episodic - trying to sneak into the Russian women's dorm, the 4th of July - linked by the overall plot of the traitor amongst the prisoners. It's broken into sequences:
A - the opening escape attempt
B - fall out of the escape attempt
C - talking about Sefton - he is suspect
D - Sefton is blamed and at the end is beaten up
E - Sefton tries to find out who does it and realises it's Price at the end
F - Sefton exposes Price and escapes.
Some of these sequence act breaks felt arbitrary eg B, C - but I guess it did ensure discipline on the structure which the piece often doesn't get.