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 help find her! Along the way, the Thea Sisters encounter Celtic legends, cryptic messages and hidden treasures on a trip that's full of surprises!

Geronimo Stilton is the pseudonym of the famous Italian writer Elisabetta Dami. She has written the famous series of books on Geronimo Stilton. She co-owns the Italian based publishing company called Edizioni Piemme. She likes to get all her ideas through her travels to places around the world.