Half way through the twenty part history of the church, things become very grim. Its not called the Dark Ages for nothing.
In this episode dealing with the ninth century we are faced with the nadir of the papacy. These popes were not just incompetent, venal or weak. They were downright wicked.
Nevertheless this episode and the one that follows will show that the light of Christ is not put out even in the Darkest of Dark Ages.