The Secret War describes how Czech agents Jan Kubis and Josef Gabck assassinated Reinhard Heydrich, a.k.a. Hitler's hangman; how French agent René Joyeuse of the U.S. Office of Strategic Services barely escaped discovery by the Germans at this hideout; how British agent Benjamin Cowburn, of the U.K. Special Operations Executive, and his team created havoc in occupied France by blowing up 13 locomotives.