Spoiler Alert Price, the security chief, played by Peter Graves, was the spy all along. Arranging for Price's timely death allows for William Holden to escape with Dunbar, a saboteur who was scheduled to be taken to Berlin and likely killed. What was this film which saw Holden take home the Oscar for Best Actor. If it will help, whistle a bit of "When Johnny Comes Marching Home".
Stalag 17