Geronimo Stilton. Thea Stilton

"An adventure down under! Moldy mozzarella! A flock of sheep at Nicky's family's Australian ranch was losing all its wool, and no one knew why. Nicky and her friends the Thea Sisters headed to Australia and set off on a tour of the whole country in serch of clues. What happened next turned out to be a truly memorable outback adventure!" -- P. [4] of cover.

When an archeologist friend of Paulina's disappears, the Thea Sisters go to Peru to look for him, where they face many dangers as they search for him and the legendary lost city filled with Inca gold that he was seeking.

The Thea sisters are off to Japan on a cultural exchange program. While they're busy exploring Kyoto and admiring the beautiful cherry blossoms, a valuable item is stolen from their friend Kumi's family. Will the five mice be able to catch the thief?

When the Thea sisters travel to New York to visit Pamela's family, who owns a pizzeria, someone threatens to burn the restaurant down, and the five mice must catch the troublemaker and solve the mystery.

"When the Thea Sisters' friend Bridget returns to Scotland for a family emergency, the five mice offer to help. And when Bridget goes missing, they have to rush to Scotland to find her! Along the way, the Thea Sisters encounter Celtic legends, cryptic messages, and hidden treasures on a trip that's full of surprises!" -- p. [4] of cover.

"When the Thea Sisters' friend Ashvin is in trouble, they rush to his aid--in India! Ashvin has been working to return the monkeys living in the big city to their natural jungle environment. But the monkeys have suddenly started stealing jewels! Can the Thea Sisters figure out who is behind this terrible theft?"--P. [4] of cover.

Attending an art class in the Netherlands, Violet journeys through the flower gardens, windmills, and canals of Holland to investigate the untimely disappearance of her friend's father, a renowned botanist whose absence is linked to a rare black tulip.

While vacationing in Greece, the Thea sisters are asked to help find an actor who has gone missing right before the opening of his play.

While on vacation in the Bahamas, the Thea sisters stumble across an old pirate map and endeavor to find the treasure, unaware that someone else is also seeking the prize.

When a thief strikes during the Venice Carnival, the Thea Sisters investigate hoping to unmask him before the festival ends.

The Thea Sisters are off to save the rainforest in Malaysia! "The Thea Sisters are heading to Malaysia. Their freinds, Latifah and Ramlee are writing a travel guide and have asked the sisters to help them research. They are stopping at all the best sites, eating all the best foods, and seeing the most amazing animals, especially in the rainforest. While exploring, they learn about a plan to cut down the trees in the forest, and Ramlee and their guide...

Young readers can join Thea Stilton, a special correspondent for The Rodent's Gazette, as she and the Thea Sisters spend the holidays in Rome.