Emily Bennett works as a therapist in Pennsylvania, helping children overcome their troubled pasts--even as she struggles to forget her own. Once upon a time, Emily was part of a middle school clique called the Harpies--six popular girls who bullied the new girl to her breaking point. The Harpies took a blood oath: never tell a soul what they did to Grace Farmer. Now, fourteen years later, it seems karma has caught up to them when one member of that vicious circle commits suicide. But when a second Harpy is discovered dead shortly after, also from apparent suicide, the deaths start to look suspicious. And when Emily starts seeing a woman who looks a lot like Grace Farmer lurking in the shadows, she's forced to wonder: Is Grace back for revenge? Or is Emily's guilt driving her mad?