For centuries, segregation and treaties have secured enduring peace between the Altered and Untouched, the two factions of Alterra; but when corruption and scientific progress threaten to cast the factions into chaos and war, two star-crossed heroines attempt to do the impossible and unite their people. After the Mass Consumption drained the earth of its natural resources, those who survived joined one of two factions: the Altered adapted by mechanically enhancing their bodies and relying on the technological remnants left behind; the Untouched retreated from technology, believing it a contributor to the Consumption, and reverted to a simplistic way of life that respected and celebrated the natural world. They have lived apart for centuries, each believing they are "fittest." But when the factions realize they are both prey to a new hunter, they desperately seek a savior who can keep them and their legacies alive. Addison Cain is a spirited Altered noble who favors the sword over conversation, much to her mother's relief. She has nothing in common with Jordana Hale, a brilliant Untouched healer who has perfected the art of keeping everyone at a distance. The two Alterrans are tapped with the responsibility of saving their people and find themselves thrown into the chaos together. As they attempt to unite their prejudiced factions, and stave off extinction, they find themselves falling in love, and learn they have much more to lose than they ever realized.