The Magician's Nephew

Exploring the attic one rainy afternoon, Polly and Digory manage to disturb Uncle Andrew in the course of his experiment. His punishment is to make them test his magic rings. The children find themselves in the Wood between the Worlds, a strange place full of magical pools which seem to be the gateways to other worlds. Before they return to London the children decide they will explore one other world but in so doing they awake and bring back to London the evil Empress Jadis who proceeds to wreak havoc. Desperate to get the queen away the children return with her (and a cabby and his horse) to the Wood and onto another land - Narnia.