Leo's determined to win the Weirdsville Dog Show this year with his scruffy mongrel, Scout. But when he finds his dead pet gerbil dug up and stuffed in a local curiosity shop, he begins an investigation which will put him and his friends in terrible danger.

Soon he uncovers a conspiracy to create a new kind of dogfood which has a monstrous effect on anything that eats it. What's more, the inventors are prepared to do anything to keep their secrets . . .