On June 16, 2016, Labour MP for Batley and Spen Jo Cox was assaulted and gunned down following a constituency surgery in Batley, West Yorkshire. Her attacker was Thomas Mair, a local man whose personal political views are said to have been antithetical to Cox's, and were thought to have driven him to murder. This documentary makes use of eye-witness testimonies to tell the story of the brutal attack that brought an end to the life of a passionate and ambitious parliamentarian. The film profiles her killer, presenting a portrait of a conflicted, contradictory man who volunteered to help people of all races, but harboured a secret obsession with Nazism and the extreme right-wing.