Most of us remember The Wizard of Oz , as the film starring Judy Garland and Bert Lahr. But the film was based on an immensely popular early 20th century Oz series. In these vels, Oz is the utopian land beyond the rainbow where threats are turned back with valor and ingenuity. Their success is due to the way they induce children to look for the element of wonder in the world around them.