Theirs is a world of opposites. The privileged live in sky manors held aloft by a secretive magic known only as the Mysteries. Below, the earthbound poor are forced into factory work to maintain the engine of commerce. Only the wealthy can afford to learn the Mysteries, and they use their knowledge to further lock their hold on society. Cettie Pratt is a waif doomed to the world below, until an admiral attempts to adopt her. But in her new home in the clouds, not everyone treats her as one of the family.

Though relations between Princess Seraphin Fitzempress and her father have been strained, Sera’s royal position has remained unchallenged. Filled with self-doubt, she struggles to grasp the Mysteries - her greatest trial yet. An education in the enigmatic magic is a necessary one, should Sera plan to rise in her station and invoke her powers during war. But the emperor’s death now leaves both Sera and her ambitious father eligible for the throne - a contest the prince regent intends to win. Even if it means an alliance with a rival empire.

For three years, Sera Fitzempress has been a pawn in a gilded prison. Disgraced and exiled from society, she has been isolated from the downtrodden she’s determined to liberate. Cettie Pratt has grown into an independent young woman, although she continues to be tested by the high society of the clouds. Advancing in the magic of the Mysteries, Cettie is also a useful tool of defense during turbulent times. The fog of war is drawing in, and with it comes a startling new enemy who may unravel secrets that both women would prefer stay hidden. 

When the emperor is assassinated, Sera Fitzempress is the noble most eligible to inherit the empire. Her upcoming marriage to the prince would cement her position. And as a champion for peace, Sera is the only promise of hope for staving off war between the worlds of Kingfountain and Muirwood. But standing between her and her enemies is just one devastating secret. Sera’s best friend, Cettie, a girl born of a lower class, has made a shattering discovery: her entire existence has been a lie.

Rescued from a world of poverty, Cettie Pratt has avoided a bleak destiny—until now. Deceived and manipulated, she has been groomed for the ultimate betrayal: to destroy her best friend and stop peace from uniting two war-torn worlds. Her path leads her to a mysterious underworld where appearances can be deceiving. Sera Fitzempress knows the value she has to her enemies. As heir to the empire, she must keep her foes at bay and prevent them from unleashing a being of unspeakable evil upon the world while fighting a brutal war.