One December night in 1942, a Nazi parachutist landed in a Cambridgeshire field. His mission: to sabotage the British war effort. His name was Eddie Chapman, but he would shortly become MI5's Agent Zigzag. Dashing and louche, courageous and unpredictable, the traitor was a patriot inside, and the villain a hero. The problem for Chapman, his many lovers and his spymasters was knowing who he was. Ben Macintyre weaves together diaries, letters, photographs,...