The Mona Mousa Code (Geronimo Stilton #15‪)‬

Enter the world of Geronimo Stilton, where another funny adventure is always right around the corner. Each book is a fast-paced adventure with lively art and a unique format kids 7-10 will love.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!