Ben wanted a Mongolian Fighting Fish more than anything: and he’d been saving for months to buy one. But when he goes to Mr Dodds's Pet Emporium with his hard-earned savings, he buys a cat instead. He didn't have a choice, really. The cat insisted.

Iggy (as the tabby likes to be called) has an amazing story to tell. He comes from a place called Eidolon, a parallel world to our own, which some call the Secret Country. It is a world full of magic and magical things – dragons, selkies, sprites and centaurs; dinosaurs, mermaids and monsters.

And as the two soon discover, Iggy is not the only animal to fall victim to the pet-store owner's devious scheme: Mr Dodds is stealing the Secret Country's magical creatures and selling them to England's rich and curious. Away from their homeland, the imported dragons, wood sprites, unicorns, and sabre-toothed tigers are rapidly becoming sick. The welfare of every creature with any connection to the Secret Country is under immediate threat. What's more, it seems Ben's mother is their long-lost queen.