Confessions of an IRA Informer (2004)

Profile of Sean O'Callaghan, a former member of the IRA, who provided MI5 with information on the terrorist organisation. O'Callaghan handed himself over to the police in 1988, confessing to the murder of two security force members. Over the course of his prison sentence, he provided information that led to the capture of many of his associates and the prevention of several terror attacks