The drama begins when the siblings, Morag and David Seton, witness the murder of the parents by a renegade named Black Angus MacGougall. David, in trying to rescue his mother from rape, is beaten and tossed into the river, believed dead. But David survives and is rescued by a hermit called Peter of the River. This leads to David meeting the Chief of Clan MacNab, and after the discovery of a secret treasure room, is placed in the hands of the mysterious Knights Templar, where he is condemned as a galley slave, but eventually wins freedom in the Holy Land. Morag is taken prisoner by Black Angus and is eventually sold to the Vikings, who, because of her developed mystical powers, view her as a Priestess, and as such she battles the Bishop of Orkney, and is able to save the son of the Jarl of Orkney from a related poisoner. Brother and sister are briefly united, only to be separated again as the saga continues.