Geronimo Stilton receives a crystal figurine of a boat as a gift from his crush Petunia Pretty Paws, and when he discovers a mysterious message inside the gift asking for help in Italy, he immediately travels to Venice to save the day.
Geronimo Stilton travels back in time to join Christopher Columbus on his voyage from Italy to America in 1492 in order to stop the Pirate Cats from becoming supreme rulers of Mouse Island.
Thea, Geronimo's sister, is invited to a college on Mouse Island to teach a journalism class, and when a student disappears, Thea and five of her students go on an adventure to solve the mystery.
A mysterious one-eyed rat is trying to steal "The Rodent's Gazette" from Stilton and the only way to save it is to be a winner on the TV game show "The Mousetrap.".