After King Arthur was betrayed by Lancelot and Mordred, a prophecy warned that Camelot would fall to the Saxons and a Wight Dragon—unless Arthur’s true heir could draw the Sword in the Stone, Caliburn. Arthur's illegitimate son, Kael, grows up as a humiliated stable boy, raised by his mother and secretly trained by Merlin and the Lady of the Lake, Elisse. After slaying the Wight Dragon and saving Princess Rhaenyra, Kael earns a place in the Round Table trials, only to face noble scorn. As Undead Armies storm Camelot and Prince Aegon confesses to Arthur’s betrayal, Kael finally draws Caliburn under Rhaenyra’s protection, awakening the blood of the Crimson Dragon within him.