On the night of August 2, 1944, a team of operatives from the U.S. Office of Strategic Services (OSS), the forerunner of today's Central Intelligence Agency, parachuted into the town of Pranjani, Serbia. Led by U.S. Army Lt. George "Guv" Musulin, the team of three was to contact Gen. Draža Mihailović, the leader of a Serbian nationalist band of fighters called the Chetniks.  He was there to plan how the United States' 15th Air Force would airlift the more than 500 downed Allied pilots the...