VONA STEWART

Hayden Fremont has outswum zombie mermaids, stared down a fanged leviathan, turned away a demon's impossible bargain, and finally freed his little sister, Sera, from the gemstone that nearly killed her. He has her back at last—so of course she's the very thing he stands to lose.

With Sera too weak to travel, Hayden and his friend Kit race to the floating kingdom of Skywallow in search of a missing diamond—and the imprisoned ruler sealed inside it—before President Altair can claim its power for his own.
Skywallow is a glittering crystal city that would sooner turn them in than help, its skies patrolled by gas-masked soldiers, man-eating pegasi, and clockwork spy crows. But its magic is failing and the entire kingdom is quietly cracking apart at the seams.

Meanwhile, far below in Briarwood, Sera is done being protected. Fighting an enchantment built to keep her sleeping and obedient, she sets out on her own, toward the ruins of Zaldana and the faint, impossible pull of the family she lost.

Hayden swore he'd keep his sister safe. But how do you protect someone who refuses to be saved? And with the diamond, their enemy, and the truth about their past all waiting at the ends of three fragile threads, will the bond between them be the thing that saves them—or the thing that finally pulls them apart?