Mark Kennedy was Britain’s longest-serving and most controversial undercover cop.

Featuring narration from Mark and interviews with those closet to him at the time, this film innovatively reconstructs the story of how an honest, well-meaning South London police officier with a wife and two kids became Mark Stone; environmental campaigner, militant activist, political extremist and undercover cop.

The film weaves together the dramtic story of his secret life and follows Mark as he tries to put his life back together and face up to his actions over the last decade.