Mirabella, Arsinoe, and Jules had Queen Katharine right where they wanted her. But when she unexpectedly killed Jules’s mother, she broke the spell that kept Jules’s Legion Curse in check. Now Jules, ravaged by uncontrollable fits of rage and violence, has to be locked away, and Arsinoe and Mirabella are tasked with figuring out their next move in the plan to overthrow their sister’s throne. But then Mirabella goes missing, and though Arsinoe doesn’t want to admit it, all signs point toward a betrayal she can’t fathom—that Mirabella has decided to ally with Katharine. Arsinoe fears that Mirabella will play their last card: that Jules, their one chance at overthrowing the throne, is barely able to speak without being heavily sedated. That the Legion Queen's loyal following of ragtag warriors is dwindling. That Arsinoe can’t see a way out of this mess. But there’s more to the picture than Arsinoe realizes. A Blue Queen shrouded in mist waiting to strike. A thousand dead queens beneath Katherine’s skin with their own aims. And an elemental with a trick up her sleeve that even the most cunning player won’t see coming. One thing is for sure: this war will come to an end…but with it, what else? Katharine’s reign? Her sisters' lives? Or the entire fate of Fennbirn?