Digory and Polly live on a city block in London where all the houses share a common attic, from one end of the street to the other. It is while exploring this attic that they enter Uncle Andrew's study. The study is not particularly interesting, except that it has some rings in it that, when worn, can transport their wearers to other places. One place is the Wood between the Worlds, which is composed of trees and a scattering of pools of water. The pools seem shallow, but when a person steps in one, that person drops though onto another planet. "It's not the sort of place where things happen. The trees go on growing, that's all," says Digory about the woods, but pools that transport people to other worlds make the place seem active enough.

The world Digory and Polly first visit is Charn, a name probably...