On June 6, 1944, just after midnight, the first paratroopers landed on the Cherbourg Peninsula in Normandy. It marked the beginning of D-Day, the largest and most complex military operation in history. In this ground-breaking two-part series, broadcaster and historian Dan Snow examines how two years of meticulous planning, espionage and the analysis of millions of three dimensional aerial reconnaissance photographs shaped that day. D-Day is also a powerful and compelling story of heroism, self-sacrifice and determination – this is perhaps the last chance to hear the extraordinary first hand testimonies of those who risked their lives to save the world from Nazi tyranny.