Charismatic, charming and complex, Sergio Vieira de Mello was the world's go-to guy, a man who could descend into the most dangerous places, charm the worst war criminals, and somehow protect the lives of the ordinary people to whom he'd devoted his life. “Sergio” tells the gripping, inspiring story of his most treacherous mission ever; a mission in which his own life hangs in the balance. The film is directed by Greg Barker.