The throne is no longer empty. Zari rules with an iron will. Relle sets the empire ablaze on dragonback.One rebuilds a kingdom. The other rises to destroy it. But something stirs beneath Vyrantha-an ancient power bound in silence and shadow. And not all betrayals come from across the battlefield. They were never meant to rule together.But when an ancient threat rises, the sisters must unite-or see their world reduced to ash.Because even dragons can't protect them from what waits beneath.