In Pittsburgh, Pennsylvania, Sam Childers addicted biker gang was released from prison and said that his wife Lynn is no longer a stripper but has converted to Christianity. One night, Sam and his best friend Donnie for a trip to a hitchhiker who threatens Donnie with a pocket knife; However Sam react and turn the tables on the stranger. Sam affected by the incident and persuaded by her mother Lynn and Daisy to join their church, and he was baptized. Sam found a job in construction straight. When he meets a preacher from Africa, he decided to visit the continent. Sam went to Northern Uganda and Southern Sudan many times and build an orphanage for victims of the Lord's Resistance Army cruel (LRA). Furthermore, he fights whenever necessary and become a legend known as The Machine Gun Preacher.