This book is very nostalgic for me. I read and listen to it alot. It's a story about two animal secret agents (a cat and a raven) who have to spy on an evil Wicht and wizard (aunt and nephew) who they suspect are responsible for many environmental atrocities happening. 
They are right and now they have to stop the biggest atrocity of them all. 

Even tho the book was realised in 1989 it's still relevant and very well written. What I like the most about this book, is that it has a happy end.
The book is very well written, but Michael Ende is also a great author.

It's a great book for a quick read, because it has very simple language (children's book), and isn't that long.