Arhianna begins her training at Dun Scáthach, where restored memories throw her into a perilous tailspin with deadly consequences.

Taliesin, desperate to gain the skills required to defend his loved ones against the ancient powers stalking them, commits to apprentice under Amergin the Bard. His journey takes him far from Caer Leon, leaving Igerna to bear the heavy secret of Morgen’s parentage alone.

Igerna raises Morgen as twin sister to her only son, Arthur. Twins are auspicious, and the people of Caer Leon rejoice that their king and queen have been so blessed. As the years pass, however, her supernatural abilities become harder to disguise. Igerna fears for her daughter's safety and takes matters into her own hands.

As Morgen and Arthur come of age, the wheel of fate sends them in separate directions. Once outside the safety of Caer Leon, those seeking to influence the pair close in quickly--some well-intentioned, others ruthless and opportunistic.

Arthur is catapulted into the position he was born to fulfill, though not in the way anyone expects. Morgen, too, rushes toward her destiny, driven by the very people who have tried most desperately to protect her from it.

In the end, Arthur and Morgen stand together on the precipice of immense power, drawing all into their orbit as they step into the roles that will inspire the songs and stories of Britain for centuries to come.