Geronimo Stilton. Thea Stilton

When the sheep on Nicky's family's ranch start losing their wool, the Thea Sisters head to Australia to investigate.

"When Paulina gets a phone call from home telling her that a friend is missing, the Thea Sisters travel to Peru to help solve the mystery. There, the five mice climb the Andes Mountains in search of a missing archaeologist. Along the way, they stumble upon clues leading them to a mysterious hidden city. Will the Thea Sisters find Paulina's friend, and the treasure of the Secret City?" -- P. [4] of cover.

"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 frien Kumi's family. Willthe five mice be able to catch the thief?" -- P. [4] of cover.

"The Thea Sisters travel to New York to cheer for Nicky as she runs the Big Apple Marathon. While there, they visit Pamela's family and have a delicious dinner at the family's pizzeria. But when someone threatens to burn the restaurant down, can the Thea Sisters catch the troublemaker and solve the mystery?"--P. [4] of cover.

"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.

The Thea Sisters' travel to India to help their friend Ashvin, who is working to return monkeys living in the big city to their natural habitat. But the monkeys have suddenly started stealing jewels. Can the sisters figure out who is behind this terrible theft?

Geronimo's sister Thea narrates this adventure packed with mystery and friendship! The Thea Sisters are headed to Italy for a ballet competition! But the mouselets aren't just there to dance -- they are there to investigate. A group is plotting to rigthe prestigious contest, and the future of the mouselets' new friend -- an aspiring ballerina -- is at stake! Can the Thea Sisters stop this scheme before it's too late? Praise for Geronimo...

The Thea Sisters are visiting friends in Spain when a mysterious theft turns their trip into an investigation! They end up hot on the trail of a secret treasure. The mouselets are in for an incredible adventure full of flamenco dance!.

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.

The Thea sisters are off to Madagascar for Adventure Camp. While on the nature preserve, they discover that endangered animals are under threat.

The Thea Sisters are headed to Venice, Italy! They'll be there for the Carnival, an annual festival that's famous for its elaborate masks. The mouselets love exploring the city's bridges and canals, and seeing the beautiful costumes mice wear to Carnival celebrations. But a mysterious thief strikes while they are there!

While the Thea sisters are at the excavation site of a dig at Hierapolis, Professor Brenninger unearths a series of priceless and very old figurines, but the Thea Sisters think the discovery may be a scam and investigate.

While attending the Festival of Time in Germany, the Thea sisters investigate the theft of a famous clock.

The Thea Sisters are off to save the rainforest in Malaysia!

"The Thea Sisters are going to New Zealand! Their new friend Charlotte wants to show them the sights, and introduce them to Didi, a skeleton of a bird that went extinct many years ago. But when they get to the mouseum, Didi has gone missing! Can they find the stolen skeleton before it is too late?"--