Coby returns to school for fourth grade determined to stay out of trouble and away from Fleshbots. However, the Fleshbots have different plans! When Coby and his best friend Antoine end up back in the underground tunnels of Marley Elementary they discover a hex bolt that will change their lives forever. They soon find that the Fleshbot problem in Marley is far worse than they ever imagined! This story is a fast paced follow up that will have the reader dying to find out what happens next!