The Magician's nephew

The story begins in London when Digory Kirke and Polly Plummer, meet. One day, while exploring the attic shared by all the adjoining houses in their terrace, they take the wrong door and surprise Digory's Uncle Andrew in his study. Uncle Andrew, a bumbling yet malevolent self-taught magician, tricks Polly into touching a magic ring, which causes her to disappear. Andrew then blackmails Digory into following her by using another ring, promising him that he will be able to bring Polly back with a different type of magic ring. The rings transport the children into a wood with many pools of water. Initially, the pools appear to be just shallow puddles but, in a parallel to the attic common to the houses on their street, the children discover that when the correct ring is worn, jumping into different pools will transport the ring's wearer to different universes...