From #1 New York Times bestselling author P. C. Cast—a sexy and magical epic of Celtic legend, perfect for romantasy fans who love Sue Lynn Tan and Thea Guanzon.

Step into the mystical world of the Isle of Skye in 200 BCE, where legends come to life and the Queen of Shadow holds court. But Scáthach is no ordinary queen. Daughter of the Underworld goddess Bēfionn, golden-haired Scáthach is gifted with the Sight, able to glimpse all the possibilities of the future and pass between the world of men and the world of gods.

Scáthach dedicates her life to training the fiercest warriors from across the land in her fortress at Lethra. But then a newcomer arrives in Lethra and upends everything about Scáthach's existence. He is Cuchulainn, the hero of Ulster, son of the Irish God Lugh. Known for his strength and bouts of berserker rage, Cuchulainn wants Scáthach to help him hone his skills and find redemption for his violent past. The Queen of Shadow reluctantly agrees to take him in, ignoring their growing attraction, and what it might mean for her destiny.

Meanwhile, Scáthach's jealous half-sister Aife threatens Scáthach’s claim to the kingdom she loves and challenges Scáthach for Cuchulainn’s loyalty. Caught in a snare of duty and desire as she navigates the perils of leadership, Scáthach discovers that her destiny may lie in the Underworld, where she can forge a future for herself and Cuchulainn by tricking death itself....