This book is about a mouse named Geronimo Stilton.This is his latest book. I recommend this book for 7-14 years old. His books have lots of pictures and really long words. Geronimo is more of a book mouse than a sports mouse. His friend Wild Willie says hes 'as boring as a raw clam. In this book he goes all the way to Japan with his friend WIld Willie in search of a lost script that has the most secret of all secrets of Karate.Wild Willie takes him to his friend and gets information in where it might be. Wild Willie and Geronimo go exactly to the right place. Then they find old ruins of what looks like a castle.They go and start digging inside it.A few hours later they find it! This a great book and you should really read it!