A young boy's fantastic and fantastical trip of discovery beyond the real world ... with a horn that goes GAHOOGA!

One hot summer Thursday, Harry meets the rag-and-bone man and his horse, and follows them through the rain door – to a whole other world behind the weather. When Harry hears a lion roar, he wants to get home as fast as he can ... but that turns out to be easier said than done. After an exciting adventure involving a home-made dinosaur and a sky-high flight through the mother of all thunderstorms, will Harry manage to escape the thundering lion and get back home?