The Clans are wrenched asunder by the Irish Civil War, while they seek to unravel an ancient religious mystery that has confounded civilization for centuries. Morgan and Tadgh support Michael Collins' Pro-Treaty Provisional government as they search for the prize to save the O'Donnell treasure with jealous Jack. Aidan and his new wife, Marjorie, fight on despite the efforts by Tadgh and Morgan to stop them. The descendant Barbary pirates and knights templar clash in their pursuit of the Clans to seize the omnipotent prize.