From Natalie D. Richards, the New York Times bestselling author of mystery books for teens, comes a pulse-pounding thriller about two teens who uncover something sinister, perfect for fans of Natasha Preston and Karen McManus.Mallory didn't want to leave home, but it wasn't safe to stay. So she sleeps at her best friend's house and spends the rest of her time at the library, doing her online schoolwork and figuring out what comes next. Because she's not going live in fear like her mother.Spencer volunteers at the library. Sure, it's community service for a stunt he pulled, but he likes the work. And it's the perfect escape from his parents' pressure to excel at school, at ice hockey, at everything. Especially after he meets Mallory.Then there is a tragic death at the library. Suddenly, what was once a sanctuary turns sinister. Ghostly footprints, strange scratching sounds, scrawled messages on bulletin boards and walls… Mallory and Spencer don't know who or what is responsible, but one