Gray Leigh knows a hundred ways to stop someone’s heart from beating, but has no idea what lies inside her own. Born a Hunter, she has spent her entire life honing herself into a weapon against Leeches, superhuman beings who feed off the pain and misery of humankind.
One rainy afternoon, the Clan Council assigns Gray to protect Simon Romero, a human biologist whose research has uncovered the existence of Leeches. As they face Leech assassins and a psychotic ex-Hunter, Simon grapples to fathom this new, violent world into which he’s been plunged. Meanwhile, Gray struggles to reconcile Simon’s kindness and pacifism with her own ascetic warrior’s life.
As the day passes into another, Gray finds herself increasingly determined to keep Simon safe, not only because it is her duty, but because she has finally found something that means as much to her as killing.