After accidentally destroying Folsom's birthday party, Fillmore and Ingrid are asked to do convention duty. However, the train convention experiences sabotage, leaving the entire convention ruined. Fillmore and Ingrid first suspect the RC Car Club to be behind it, but the evidence points in the other direction.

Scooter thefts are up, and the Safety Patrol faces a challenge from student activist Derek Minna, who establishes B.A.G.A.S.T. (Boys And Girls Against Scooter Theft), a scooter and rollerblade equipped task force that he intends to ultimately replace the safety patrol. Fillmore and Ingrid trace the thefts to the Metal Shop and infiltrate the gang in an attempt to take down the culprits.

The Ultrabox, the hottest new game system on the market, makes its debut at X, and everyone wants one—including "The Maestro," a gaming mastermind who will stop at nothing to get it. Fillmore and Ingrid track him down, but the Ultrabox is stolen while he's in custody. It looks like a copycat is on the loose.