In this stunning ninth book in the New York Times and USA TODAY bestselling Keeper of the Lost Cities series, Sophie and her friends discover the true meaning of power—and evil. Stellarlune—and the mysterious Elysian—might be the key to everything. But finding truth in the Lost Cities always requires sacrifice. And as the Neverseen’s plans sharpen into terrifying focus, it appears that everyone has miscalculated. The Lost Cities’ greatest lie could destroy everything. And in the battle that follows, only one thing is certain: nothing will ever be the same.