The Mona Mousa Code - Geronimo Stilton

The world s most famouse painting is hiding a big secret! An X-ray of the Mona Mousa reveals a strange riddle. Solving the clues takes Geronimo to the most dangerous parts of the city, but facing the hair-raising rollercoasters and vicious octopuses is all worth it for the amazing treasure at the end of the trail. Isn't it?