Ben Macintyre

'The Man Who Never Was,' by Ewen Montagu, remains the best book about wartime espionage written by an active participant - incomplete, and dry in parts, it nonetheless summons up the ingenuity and sheer eccentricity of those who played this strange and dangerous game.

'What if?' history is a tricky game, but there is no doubt that the senior planners of D-Day - including Eisenhower and the British general Bernard Montgomery - believed that the Double Cross operation had played a pivotal role in the victory.

From an actor's point of view, you never really like to hope that anything will go beyond the pilot. I'd always say to my agent every time I filmed a pilot, 'Great! Well, I'll see you at pilot season.'