If they can’t solve his riddles, their friends will pay with their lives. Scrawny outsider Jay receives a strange phone call on a school trip to Titanium Tower. The voice on the other end calls himself Z. And he has trapped Jay’s classmates in the elevator at the very top of the skyscraper. Jay finds himself with no choice but to try and solve Z’s deadly riddles. Not only that, he has the worst person possible helping him: Hudson Hamm, the school’s star athlete and resident thug.Soon Jay and Hudson are on a high-stakes scavenger hunt around the city. If they can’t beat Z at his own game, their classmates and family members will pay with their lives.