Kaelen hides in the ice fields, while his son Thorne grows up unaware of his royal bloodline, working as a low-rank Karl at a fishery. Thorne longs for a simple life with his betrothed Astrid, but this quiet hope is shattered when Jarl Hrafn's heir Rurik humiliates him, takes Astrid, and throws him into a dungeon. A blood oath rune on Kaelen's chest feels every wound Thorne suffers, rousing him from hiding. The jarl submits to him, his agent Hersir Bjorn swears loyalty, and the First King's Sword blazes for his blood. Berserker chieftain Finn arrives to kill the king, only to find himself bound to Kaelen by an ancient slave seal. In the final reckoning, Rurik is cast into the ice abyss, Astrid's ambition ends in mockery, and Thorne awakens his royal blood and is named crown prince. Beneath the green aurora on a fjord cliff, the High King kneels to Elora and offers her a shared throne.
