Geronimo Stilton is the editor of the Rodent's Gazette, the most famouse paper on Mouse Island. In his free time he loves to tell fun, happy stories. In this adventure, Geronimo has to face his worst enemies, the Pirate Cats, who have discovered a way to travel back in time and change history... Work on the transcontinental railroad connecting the East and West coasts keeps suffering mysterious mousehaps. Can it be the dastardly work of Catardone and his band of Pirate Cats? In the unlikely role of Deputy Sheriff, Geronimo Stilton must once again save the future by protecting the past!