Hundreds of spies betrayed their countries during the Cold War, often motivated by ideology, or financial reward. Jeff Carney was different - he was a lonely, gay US airman who dreamed of a new life in East Germany. Years later, he sees parallels between his story and that of Chelsea, formerly Bradley, Manning.

It was the middle of the night in April 1983, when Jeff Carney approached Checkpoint Charlie. His steps grew shaky and he began to sweat.

As he stepped across the painted white line that separated East and West Berlin, he thought he was safe. He thought he was going to live in the east. He couldn't have been more wrong....