The Mona Mousa Code : Geronimo Stilton 15

Do you like art? I do! So when Thea heard that there was a secret map hidden beneath Mouse Island's most famous painting, the Monamouse, I knew we had to get the scoop! Together we began to investigate, and soon we discovered secret clues that led us to the most fabumouse secret. And it all lay beneath the streets of New Mouse City!