Oh no! The famous Diamondo del Mondo has been stolen! There's something fishy going on. And no one knows fishy quite like . . . Inspector Penguin! Spot the clues throughout the book to help Inspector Penguin solve the mystery!

Who could have broken into Baron von Buffetworth's super-secure top-secret safe? And where have they taken his precious diamond?

There's only one detective who can solve this mystery: Inspector Penguin! That is, if he can keep his mind off tuna long enough to find some clues . . .

An exciting, interactive detective story from the team behind Secret Agent Elephant.