In this taut spy thriller from Academy Award-winning director James Marsh, Collette (Andrea Riseborough), an IRA soldier and single mother, falls into the hands of the MI5 during a botched London bombing attempt. Mac (Clive Owen), her handler, offers her a choice: turn informant on her family or go to prison. Fearing for her son's welfare, she returns to Belfast, raising suspicions. With Mac's boss (Gillian Anderson, "The X-Files") further endangering Collette's life through her own agenda, Mac is forced to take greater risks to protect Collette—and both feel the net closing in.