Jayden Jones is missing. Everyone thinks he ran away. His best friend, Zoe Ross, knows they're wrong. Zoe's search leads her to the Seventeen a secret group chat, used by anonymous teens to blackmail the powerless. To join, you have to put on a mask and record yourself completing a challenge. The challenges are always illegal. Sometimes dangerous. Maybe deadly. Who are the Seventeen? What have they done to Jayden? And what will they do to silence Zoe?