Guildenstern, the Science Department's tarantula mascot, has been poisoned, and the prime suspect, Eric Orben, has escaped into the city. Fillmore is given a permit to go out and track him down, but he has to contend with a relentless opponent from his bad-boy past.
Facing expulsion under Principal Folsom's new "Three Strikes, You're Out" rule, Fillmore must protect the only person capable of clearing his name to a crime he has been framed for—the destruction of a giant Folsom statue made out of 12,000 pieces of macaroni.
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.
Fillmore and Ingrid investigate the mysterious vanishing of a student named Alexis, only to find that all reports of her have vanished from the school, and she's even been taken out of pictures. Meanwhile, someone is working on a computer virus called Electric Haircut, which must be stopped before it causes any irreparable damage.
Something's down at the X Middle School Open—professional golfers are failing at games, and foul play is suspected. Normally, Fillmore would be all-up for an undercover job like this, but something in his past is making him hesitate.
Spring break has arrived, so Fillmore's taking the time to visit his former partner, Wayne Liggett. In Wayne's new school, something about the Safety Patrol stinks. The prize pralines of the school have been stolen, and the prime suspect is their Patrol Sheriff Thrift—who just so happens to be the son of their principal.
Former delinquent Cornelius Fillmore saw the light, and now fights on the side of justice at X Middle School. Joining him is Ingrid Third, who has a photographic memory. Together, Fillmore and Third fight all those who attempt to break the rules at X, all while keeping Jr. Commissioner Vallejo off their backs and trying to please the school's overly-image-conscious Principal Folsom. Fillmore! is an American animated television series which was produced by Walt Disney Television Animation. The series was created by Scott M. Gimple and directed by Christian Roman. It was the last series produced by Walt Disney Television Animation alone, without association with Disney Channel.