During the Vietnam War, perhaps the US Army’s most secretive unit was the Studies and Observations Group (SOG). This unit conducted reconnaissance missions, captured enemy prisoners for interrogation and rescued American POWs. It also ran teams of clandestine agents, and conducted psychological operations. The leader of this group in the mid-1960s was a legendary Army officer, Donald Blackburn. Listen to author Mike Guardia describe Blackburn’s colorful life in this event which took place on 16 February 2012.