Morgan Freeman explores how religions have developed ways to fight back against sin. He meets an executioner who had a change of heart, uncovers the origins of self-flagellation, and talks to John McCain's Vietnam jailer about sin.

Morgan Freeman explores what holy laws mean for different religions around the world and the punishments awaiting those who disobey. He investigates how the eruption of Vesuvius was seen as divine retribution. He sees the oldest existing copy of the Ten Commandments.