In the Carpathian Mountains, Ilinca survives tragedy and accepts Lucifer's offer to become his architect of souls. Unable to inhabit human flesh, Lucifer uses forbidden alchemy and the remains of martyrs to construct a perfect vessel. Her power lies not only in the creation of bodies but also in her pact with the Grim Reaper to traffic in spirits, becoming the leader of an army of corpses that return to life each morning.