When Louise Williams receives a message from someone left long in the past she feels sick. Maria Weston wants to be friends on Facebook. Because Maria Weston has been missing for over twenty-five years. She was last seen the night of a school leavers' party, and the world believes her to be dead. Particularly Louise, who has lived her adult life knowing herself responsible for Maria's disappearance. But now Maria is back. Or is she? As Maria's messages start to escalate, Louise forces herself to reconnect with the old friends she once tried so hard to impress, to try to piece together exactly what happened that fateful night. But when another friend's body turns up in the woods outside their old school, Louise realises she can't trust anyone and that she must confront her own awful secret to discover the whole truth of what happened to Maria...