There‘s a face of the Second World War that takes place in secret, behind enemy lines, and with very high stakes: Daredevil missions, dangerous assignments and secret operations that continue to mystify experts. We take a fresh look at some of the most notable secret missions of the Second World War, including the 1943 Gran Sasso mission to free Benito Mussolini, the hair-raising kidnapping of a German commander in Crete by British special forces, the assassination of Reinhard Heydrich in Prague, and the cold-blooded killing of the American-appointed mayor of Aachen in the last months of the war.