When Professor Greenfur changes color from green to orange, the spacemice travel to his home planet of Photosyntheson to investigate and find that his relatives are all being threatened by tiny aliens with sharp teeth.

"Something is wrong with Gorgo, the monster in the moat of Cacklefur Castle! Creepella discovers that he is lovesick for the monster Blobbina, who also happens to be a famous movie star. But when Creepella delivers Blobbina a love letter from Gorgo, she finds out Blobbina has disappeared! Creepella and Billy Squeakspeare head to Horrorwood to search for the missing Blobbina. Will they ever find her?"

Grandfather Shortpaws sends Geronimo Stilton on a hunt for his old friend, the Red Bandit, in Arizona.

Geronimo Stilton's ancient ancestor Geronimo Stiltonoot is back in another prehistoric adventure. Geronimo Stiltonoot and his family are off to find a cure for Grandma Ratrock's aches and pains. She's heard that a remedy hides in a legendary valley, and Geronimo isn't even sure it exists. Little does he know that getting there will be an adventure among geysers, volcanoes, and rivers of molten lava.

Traveling to Cleanix to investigate why floating space junk has engulfed MouseStar 1, Geronimo finds that the planet's alien inhabitants are extremely wasteful and face the threat of rebellion by the robots they've thrown in the trash.

After receiving a mysterious message summoning him to a meeting, Geronimo Stilton finds himself back in the Kingdom of Fantasy, summoned by the Elves, who want him to travel to the Great Explanatorium to find an answer to the earthquakes that are threatening the Kingdom.

Geronimo Stilton's ancestor, Geronimo Stiltonoot, must prove his innocence when the grand prize from the Cavemouse Idol competition is stolen.

"Old Mouse City is in an uproar. The most precious artifact in the mouseum -- the Stone of Fire -- has been stolen! Geronimo Stiltonoot and his cavemouse friend Hercule Poirat are on the case. It's up to them to retrieve the stone from the ferocious Tiger Khan and his band of fearsome felines!"--Page 4 of cover.

Geronimo Stilton's ancient ancestor, Geronimo Stiltonoot, and his family save a young dinosaur from the river. Can Geronimo get him back to his herd before he causes a disaster?

When they receive a damaged message in a bottle from the Oofa Oofa rodents in the ancient far north, Geronimo Stiltonord and the micekings set sail to Oofadale but are attacked by a band of dragons while on their voyage.