In time for the 100th anniversary of the publication of The Wizard of Oz, popular mathematician, pseudo-science debunker, professional literary eccentric and first chairman of the International Wizard of Oz Club Gardner (Classic Brainteasers; The Annotated Casey at the Bat) has cooked up this rather disenchanted bagatelle, mixing fin de (this) siecle satire with references to several childhood classics. As one would expect from the world's premier math puzzle expert, the book contains a little math puzzle. Dorothy, the Scarecrow and the Tin Man want to return to earth for a visit, but how can they get through the fourth dimension that separates Oz from earth? They do find an answer that is topologically sound, although not exactly easy to understand, and arrive back on the planet in time for 1998, where a good movie producer has summoned Dorothy to earth as part of a publicity stunt for a production of one of the Oz books. Another, evil movie magnate has other plans. Unfortunately, the magic of the Oz books doesn't survive arch references to Mayor Giuliani and TV newscasts. Although Gardner's introductory remarks about Oz are inspiring, this sequel (like the Scarecrow after his encounter with the Wicked Witch of the West) is just too disjointed to work. Color illustrations and spot art by Ted Enik.