Review: Overall, I thought this book was very good. However, when comparing it to the other books in the series, it's a bit, for lack of a better word, different. For instance, all of the other books in the series deal primarily against one evil organization: SPYDER. On the contrary, this book, Spy School Revolution, has to do with a different evil organization: The Croatoan. So, it's definitely odd for people who have truly enjoyed all of the other books in this spectacular series. Although, I do enjoy that Stuart Gibbs, the author, developed a lot of the characters' stories. All things being considered, I give this book a solid 4 stars.