This book is an utter joy to read, with its fast-paced, imaginative plot, driven along by short snappy chapters. The idea of a secret service agency run by animals seems completely feasible due to the skilful writing of Anne Miller, and the black and white illustrations by Becka Moor (who has worked on many children's books) are a perfect complement to the text. The explanations of Mickey's code-breaking techniques will be fascinating to children, and are a nice introduction to cyber security which is touched on in the primary school computing curriculum.