Joe was just a teenager when his kid sister Annie went missing. He’d been hanging out with a troubled group of friends in his hometown of Arnhill, exploring a supposedly haunted abandoned mine when she disappeared for 48 hours. But the thing is, Annie came back--she just wasn’t the same girl. And his sister was only one of the group’s casualties.

Joe left Arnhill with no desire to return. But somehow, he always knew he’d be back. When he receives a mysterious message that implies what happened to his sister may be happening again, he bluffs his way into a teaching job at the local high school and begins to investigate. The first lead? A recent-murder suicide in which a mother brutally killed her young son and wrote three chilling words in blood on the wall: Not my son.