The jewellers of Muskrat City are in trouble. A thief has been stealing precious diamonds, and the thief is...invisible! Can the Heromice protect Duchess Marilyn Mousekovia and her precious gemstone during her visit to Muskrat City? And more importantly, will they catch the elusive Invisible Thief?
Series: Geronimo Stilton: Heromice
Paperback: 128 pages