In New York Times bestselling author Wendy Corsi Staub’s electrifying new thriller, a mother races to save her daughter beforeher darkest nightmare comes true. Sacred Sisters Catholic girls’ school has hardly changed since Jen Archer was a student. Jen hoped her older daughter would thrive here. Instead, shy, studious Carley becomes the target of vicious bullies. But the real danger at Sacred Sisters goes much deeper.The only person Carley can talk to is "Angel, " a kindred spirit she met online. Carley tells Angel everythingabout her younger sister, about school, about the sudden death of her former best friend. Angel is her lifeline. And Angel is closer than she knows.When another schoolgirl is found dead, Jen’s unease grows. There are too many coincidences, too many links to her past. Every instinct tells her that Carley is the next target. For someone is intent on punishing the guilty, teaching the ultimate lesson in how to fear . . . and how to die.