Small creatures have been turning up throughout Charlotte, North Carolina, mutilated and displayed in a bizarre manner. But one day, Temperance Brennan gets a disturbing call. The perp is upping the ante. This find could be human. Tempe visits the scene and discovers that the victim is a dog. As one who has always found animal cruelty abhorrent, Tempe agrees to help apprehend the person responsible, and she acquires an equally outraged ally in semi-retired homicide detective Erskine “Skinny” Slidell. Then a woman is found disfigured and posed in a manner that mimics the animal killings. Subsequently, people Tempe cares about begin to go missing until it becomes clear she is being taunted, the target in a sick game that has her and Slidell racing against a ticking clock and facing a terrifying question: “What is pure evil?”