Geronimo's adventurous sister Thea narrates this fabulous adventure that's packed with action, mystery, and friendship!In this exciting adventure, the Thea Sisters are off to Paris to visit Colette's fashion-designer friend Julie. But when Julie's designs are suddenly stolen, the girls must search the city of Paris to catch the thief and save the fashion show. Readers will love following the clues to help the Thea Sisters solve the mystery!

Geronimo's adventurous sister Thea narrates this fabulous adventure that's packed with action, mystery, and friendship!The Thea Sisters are boarding the famouse Orient Express for a journey from Paris to Istanbul! The train is on a special trip to return a precious wedding dress stolen years ago from an Istanbul museum. But there's a rumor that the mysterious Acrobat Thief will steal the dress from the moving train! The Thea Sisters are determined to foil this super-sneaky mouse's plans.

The Thea Sisters are on a magical adventure! The Thea Sisters' next adventure to the Kingdom of the Fairies!

Join Thea Stilton and the Thea Sisters on an adventure packed with mystery and friendship! The Thea Sisters are heading to Malaysia. Their friends, 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 they are exploring they learn about a plan to cut down the trees in the forest and Ramlee and their guide go missing! Can the sisters track down their friend and save the forest?

The Thea Sisters are five fun, lively students at Mouseford Academy on Whale Island, who want to be real, live journalists, just like their hero, Thea Stilton. Between classes, friendships, crushes, and some bizarre mysteries to solve, they find life to be a never-ending adventure! Colette, Violet, Pamela, Nicky, and Paulina are working on a historical restoration when they learn about an ancient Viking vessel that sank off the shore of Whale Island. Rumor has it that the ship is full of treasure, and what's worse, some shadowy figure is plotting to steal it! If Mouseford's best investigative journalists can't crack this case, Whale Island will lose one of its most important cultural artifacts before it's even found.

Join Thea Stilton and the Thea Sisters on this adventure packed with mystery and friendship! The Thea Sisters are visiting friends at a lively festival in Spain. But the theft of a precious fan turns their trip into an investigation! They end up hot on the trail of a secret treasure . . . but they're not the only ones searching for it. Can the mouselets solve the mystery in time? It's a mission full of flamenco dance!

Join Thea Stilton and the Thea Sisters on an adventure packed with mystery and friendship! The Thea Sisters spend the holidays in Rome!