Denver and Jeremy enter a wacky game show only to find they're competing against the team Morton Fizzback and Professor Funt.

A boy genius, Freddy Facknitts, invents a time machine that sends Denver and Morton Fizzback into the past and into the middle of a crazy caveman competition called Mammothball.

Denver and Mario take a job as children's entertainers only to incur the wrath of Douggie, the Dancing Clown, who tries to sabotage Denver and Mario's entertaining efforts.

Decked out in caveman attire, Denver and the kids form a rock group (B.C. Rock) to compete in the city wide talent contest. Freddy Facknitts also form a group called Roborock (rock'n'roll robots). But Morton Fizzback and Dr. Funt steal the robot band right before the contest and the kids must go after them.

Denver, the boys, and Freddy Facknitts attend a comic book convention, dressed as their favorite comic heroes

Wally's pretty, female pen pal from Sweden, Inga Svinga, is coming to visit

Denver's mistaken identity at a golf tournament sets Fizzback and Funt off on a high-tech cheating spree while the golf course groundskeeper tries to capture what he believes to be the Loch Ness Monster.

When Denver, Casey and Freddy Facknitts become accidentally airborne in a Freddy-designed hover craft, the city starts to buzz with rumors of UFO sightings!

Mario and Shades get jobs working for competing fast food restaurants, and it jeopardizes their friendship.