In a California desert, a once glittering Hollywood hotspot, the Byron Hot Springs Hotel, gets converted during World War II into a top-secret interrogation center for high-value German and Japanese POWs. Before being shuttered, this high-tech facility called Camp Tracy gathered reams of valuable wartime intelligence.

Graffiti scratched into the walls of a military base on the British coast sheds light on a secret raid against the Nazis; the story left behind by the soldiers does not match the rosy picture that was painted by the media...