The Magic City tells the story of Philip, who goes off to live with his new step sister Lucy. He has trouble adjusting at first, thrown into a world different from his previous life and abandoned by his sister while she is on her honeymoon. To entertain himself he builds a giant model city from things around the house: game pieces, books, blocks, bowls, etc. Then through some magic he finds himself inside the city, and it is alive with the people he has populated it with. Some soldiers find him and tell him that two outsiders are bound to show up.