I've just read Laura Hillenbrand's book about Louis Zamperini, "Unbroken: A World War II Story of Survival, Resilience, and Redemption". It's worth a read but you can also get an ouline of his story from these YouTube videos:
The rest are after the break. The main link to Japan starts in the second video when Zamperini is captured during the war and sent to Ofuna Prison. As the link there shows, several of the guards at the camp were later convicted at the War Crimes Tribunal. He was then sent to Omori in Tokyo where life wasn't any easier.