The Great Escape
Paul Brickhill
In 1944, hundreds of Allied airmen at Stalag Luft III spent months digging tunnels for a mass escape from the German POW camp. Brickhill helped plan the breakout; of the 76 men who got out, most were recaptured and many were killed.
Brickhill is good on the practical side: how they dug the tunnels, what went wrong, and how the camp was run. You get a sense of the people as well as the plan. I had seen the film before reading it, and the book filled in a lot I did not know.