For more than four years, Martin McGartland lived the remarkable double life of a secret agent. To the IRA he was a trusted Intelligence Officer and an integral member of an active service unit. To the British Government, he was 'Agent Carol'. In this double role he is credited by Critish Intelligence with saving the lives of at least fifty people. Every time he tipped off the authorities he risked detection and yet, heroically and fearlessly, he continued to pass on life-saving information. Finally his cover was blown and he faced certain execution ... This is the story of his survival.