This week Roy meets a former drug dealer who's become an unlikely and controversial hero in an African war zone. Victims of the continuing conflict in South Sudan and surrounding areas have often been children, taken by armed groups and turned into child soldiers. In an area where many have been snatched, this American preacher has established a number of orphanages. But he's far from the usual image of missionary or aid worker. An ex-alcoholic, rough-living biker, he has led his own heavily-armed group of soldiers to defend children at risk in the conflict, sometimes re-capturing them in fights with the notorious Lord's Resistance Army. A Hollywood film has told the dramatic story of his life, and five years ago he won a Mother Theresa Award for international social justice. He's now on a European tour, and is speaking in Newport this week. His real name is Sam Childers but he's best known as the Machine Gun Preacher.