Twelve-year old Tallie knows she shouldn't break Mother Kyraisa's strict rule and summon the lights again. But after another orphan wakes up crying, she does it anyway. When Mother Kyraisa catches Tallie, the ancient nun evacuates the orphanage, ordering it burned immediately. She then crams Tallie into a lead-lined coffin and flees into the desert, whipping the horse the whole way. With no memories, no heart, or even a name, X is a monster. Fiercest of the Bestials, his predator's instincts are controlled only by the oathchain binding his life-threads to the Regent's will. When a flash of apostate magic betrays the hiding place of the late Queen's daughter, the Regent dispatches X to kill the child-her niece and the true heir to the throne. Following the hidden princess's soulprint, X transforms into a falcon, tracking Tallie to her hiding place. Poised to kill her, Tallie surprises him with her trusting heart and a sincere request for help. Tallie's friendship and trust awaken a small spark of humanity inside X, creating different bonds than he's ever experienced. But he remains a monster, bound by instinct and unbreakable oaths. Helping Tallie triggers a ferocious battle, as X fights his primal nature for her life-and his only hope of redemption. Meanwhile, Tallie grapples with the tragedy of her past and the burden of her identity as crown princess. Filled with tremendous rage at her aunt, Tallie finds access to immense power-enough to destroy her enemies, but possibly her own soul.