Geronimo Stilton #30 The Mouse Island Marathon by Geronimo Stilton is the 30th book in the Geronimo comic book series. Authored by Elisabetta Dami for children, the Geronimo series is the story of a mouse by the same name. Geronimo Stilton, the lead character in the series, is the editor of ?The Rodent?s Gazette? in the fictitious New Mouse Island. He also gets involved in some adventure of his own. In the Mouse Island Marathon, Geronimo Stilton gets a chance to participate in the Marathon race due to certain circumstances. Geronimo is not sure whether he should take part in the race. Geronimo is extended all the support by his friends and family so that he completes the race successfully. The story revolves around Geronimo?s participation in the race.