Fifth in a 13-part series of investigative programmes from the BBC regions.

Martin McGartland worked undercover in the IRA as one of the RUC's most important agents. In the course of his work he helped to save dozens of lives by tipping off the RUC about planned attacks. When his cover was finally blown, he was taken to an IRA safehouse for questioning and almost certain death.
Although guarded by three armed men, he jumped from a third-floor window to escape. Since then he has changed his identity many times to escape the IRA's retribution.
This programme follows the remarkable story of McGartland's double life and his escape from the IRA, his time in exile and his journey home to Northern Ireland in disguise.
(First shown on BBC Northern Ireland)