Mom?s new pottery obsession leads Mona and her friends to investigate the pottery studio where they discover the clay is a little too life-like?in fact it seems to be alive!/ When Lily flushes Charley?s Mer-monkeys down the drain, the consequences appear to be disastrous.
Charley accidentally awakens the all-powerful Viking god Thor when he removes his statue from the museum. / After Mona, Lily and Charley discover that Mr. Piper the substitute music teacher is an ogre they realize they must stop him before he uses his spellbinding clarinet to transform everyone in town.
There seems to be something diabolically strange about Zelda the fortune teller./ Mable, the owner of the local health food store, has gone missing and fairy expert Lily senses big trouble. It turns out Mable is really the fairy Queen Mab and she?s been kidnapped by mischievous fairies who will wreak havoc in town unless the kids can stop them.
When Fang and the other cats in town start behaving strangely and then start disappearing, Mona's investigations lead to the factory, where the feline like Dr. Purrman makes his very popular cat food./ Mona and her friends discover who is behind the recent shark sightings at the local beach.
Mona and her pals have their hands full when Neptune, the god of the seas, discovers the long lost missing continent of Atlantis right under their town and wants to restore it to its former glory./ The unseasonable early appearance of shadflies from the swamp behind Mr. McCaughllin?s house arouses Mona?s suspicion and leads to a full fledged effort to stop an inter-terrestrial invasion.
When Miss Gotto?s bossy older sister substitutes for her, Mona uncovers a horrible plot. Roberta Gotto is really a robot and she and her kind intend to take over the school. / After the kids encounter a maniacal wizard at the new Laser Dome, everything they imagine starts to come true.
If Officer Halcroft is going to win Mona, Charley and Lily are going to have to battle some very devious gremlins who just might be under the control of the unscrupulous Wilson Rollins. / When the kids all attend circus camp, run-ins with George and Angela turn out to be the least of their worries.
Charley?s opportunity to make a little babysitting money turns into a close encounter with a family of aliens and their identical triplet sons./ Zapman decides to strike out on his own after Mona embarrasses him in the schoolyard. But it looks like it?s going to take all three of our heroes working as a team to defeat a prank happy Coyote god who's on the loose in town.
While working in a fast food restaurant for Career's Week, the kids uncover an alien plot to enslave the whole town through an extra-special secret sauce. / When the old school bus is brought back into action George gets a very rough ride from the ghost inhabiting it.
While some are saying the Seville Theatre is just old and falling apart Mona knows that it?s being haunted by a ghost that escaped from the big screen./ When Mona, Charley, and Lily go on a school ski trip they encounter a series of mysterious snowy incidents and Mona concludes there?s only one rational explanation, the mythological Yeti has made the ski hill its home.
Mona and her friends enter a sand sculpture contest and unwittingly awaken the spirit of a mischievous sandman who seems to be bent on putting the whole town to sleep./ When Count Von Kreepsula and his arch rival Dr. Nefarious go missing from a comic book Mona leads the kids to a comic book convention where an amnesiac Von Kreepsula is about to fall into the clutches of his enemy.
The aging but still phantasmagoric Rockin? Reptiles are on a reunion tour that just might transform the kids? strange dressing and strange talking mothers into eerie reptiles./ After suffering through a few weeks without one sighting of a ghost Mona and company are given cause to suspect that a vacuum cleaner salesman is sucking away ghosts in a super duper new vacuum cleaner.
Mona, Charley and Lily become alarmed when there's a local garter snake population explosion. / When the new weatherman Jonathan Jupiter is able to flawlessly predict the weather Mona and pals start to wonder if he isn?t controlling the latest terrible storms via the flying saucer he insists is just a weather balloon.