Billy's science project goes horribly wrong. Billy, Zeke and Marsha must find the Cheeserator.

Zeke, the King of Calzones, must defend his title. Billy invents a grafting machine.

Marsha learns she has missed her date with her summer camp crush Greg Hastings; Zeke feels intimidated by a primitive tribe called the Troggies, who can do everything better than he does.

Marsha starts a newsletter about Subterranea-Tania and Billy desperately wants to know what she wrote about him; Billy strikes up a friendship with the sludge-obsessed Count Wretcher, who offers to fix the Cheeserator for his own nefarious plans.

A grass nymph called Judy falls head over heels for Billy, who is too busy dealing with a crush of his own; Billy becomes the new apprentice to Subterranea-Tania's resident sorceress, Hag Witch.

Marsha becomes convinced that Billy has been cursed after he takes a rock from a sacred patch for scientific analysis; a barbarian named Zartran moves in with Billy and his friends and entertains them with stories of heroic battle.