It is 8th century Ireland and the land is littered with ambitious chieftains and petty kings lobbying for power and status in a time where no one leader has been duly recognized. Devin is the eldest daughter of the petty king, Attus, who dominates the vast north, called Ulaid. Favored by her influential father and having no interest in the crooked path of politics, Devin is allowed to pursue her own course. She chooses the mysterious direction of the healing arts, learning the ancient ways of her Celtic ancestors alongside the druid Oran, a trusted member of their clan and her father's advisor.

In a sudden act of vengeance by their greatest rival, Bram, tragedy befalls their great house and leaves the family shattered and grieving. Propelled onto a great seat, she must learn to honor her ancient ways in a land dominated by Christianity and men. Jealousy mounts from her sister, Una, a powerful yet petty woman who secretly plots against her. With odds stacking against Devin, she finds partnership and solace with Tristan, a soldier in her father's army, and the man who becomes her lover. Their love is all-consuming, and distracting, as she battles enemies near and far that covet her great seat.

Devin must overcome betrayals, wars and intrigue as she discovers her true strength as a woman and a warrior in a time where no one can be trusted.