Across thousands of planets in the Krey Empire, all humans have a single title...slave. Born to oppression, Siena is an ordinary young woman, until an act of defiance leaves her scarred and marked as a rebel. She's sold to Ero, a fallen Krey with a desperate plan to redeem his once-powerful family. He intends to enhance slaves by altering their genetic code, increasing their value through an illegal experiment. Reklin, a bone-armored soldier, hunts them both. His orders come from a mysterious source, but his loyalty to the Empire has no limits. Noble, soldier, and slave, they are about to discover a dangerous truth–that humans can be augmented. But none can predict the abilities they'll unlock, or the rebellion they'll unleash.