"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 search of clues. What happened next turned out to be a truly memorable outback adventure!"--Pages [4] of cover.

"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 friend Kumi's family. Will the five mice be able to catch the thief?

"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?"--Page 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!"--Page 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.

"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 rig the prestigious contest, and the future of their new friend -- an aspiring ballerina -- is at stake! Can the Thea Sisters stop this scheme before it's too late?"--Page 4 of cover.

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 on vacation in Greece, the Thea sisters make friends with a company of actors who are rehearsing for a play that's about to open. When an actress sprains her ankle, Colette ends up standing in for her. But suddenly, right before the performance, the lead actor goes missing. Can the mouselets find him in time for the show to go on?" --

The Thea sisters are off to Madagscar to a wilderness survival competition. They soon learn that they are not alone in the nature preserve and endangered animals are under threat.

Thirteen-year-old Dan Cahill and his older sister Amy race against time to find an ancient map that has not been seen for half a century and use it to redeem their family members who have been kidnapped by a sinister organization called the Vespers.