Eric Thorgrimursson, nicknamed "Brighteyes" for his most notable trait, strives to win the hand of his beloved, Gudruda the Fair. Her father Asmund, a priest of the old Norse gods, opposes the match, believing Eric to be a man without prospects. Deadlier by far are the intrigues of Swanhild, Gudruda's half-sister and a sorceress, who desires Eric for herself. She persuades the chieftain Ospakar Blacktooth to woo Gudrida, making the two men enemies. Battles, intrigues, and treachery follow.