Her guardian angel was pushed. Keiron was never meant to be anything other than a hero. Born high above in a place of war and deception, he is Heartborn, a being of purity and goodness in a place where there violence and deceit are just around every corner. His disappearance will spark a war he cannot see, for Keiron has pierced the light of days to save a girl he has never met, for reasons he cannot understand. Livvy Foster is seventeen, brave, and broken. With half a heart, she bears the scars of a lifetime of pain and little hope of survival. Until Keiron arrives. In the middle of a brewing war and Livvy’s failing heart, Keiron will risk everything for Livvy, because a Heartborn’s life can only end in one way: Sacrifice. Fall with Livvy and Keiron as they seek the truth about her heart, and his power, and what it means to love someone who will give their very life to save you.

Livvy Foster has a new heart, home, and place in sky of her new world. The fall of Sliver was only the beginning of a civil war. Angels from across the sky challenge each other to lead a world where time and magic are tools for war. When House Selinus attempts to become the supreme power in a distant future, they confront a goddess who is older than time itself—and she'll stop at nothing to get the one soul who escaped her deadly Livvy. With deceit, war and love swirling in the clouds above a shattered world that was once Livvy's home, she'll be asked to do something a girl with a broken heart never thought possible. Fight for Windhook. Fight for her world. Take wing with Livvy, one heartbeat at a time.