Harry loves the Hideout that he built with his Grandad. In it he keeps the very special book that Grandad gave him to help him to learn about the Person who made the whole world. But it's not just any book - it's a portal to Bible times.
Harry starts to learn about the meaning of prayer after he sees Jesus talking to His Father in the same way that Harry talked to his own Dad. Then, after playing detective to find some missing keys, he realises from hearing Jesus' stories that God searches for lost people in the same way that he had searched for the lost keys.