‘They called us the Mercies. They said we were shadows, ghosts, and if you touched our skin we dissolved into smoke.’ Frey, Ovie, Juniper, and Runa are the Boneless Mercies — girls hired to kill quickly, quietly, and mercifully. Men do not want to do their sad, dark work. But Frey is weary of the death trade and dreams of a life bigger than the one she’s been dealt. So when she hears of an unstoppable monster slaughtering men, women, and children in a nearby town, she decides this is the Mercies' one chance out. But Frey soon learns the real meaning of sacrifice, and the cost of guts and glory. Her actions may change the fate of girls in the world forever.