The Glass Cat of Oz is a modern Oz novel, written by David Hulan and illustrated by George O'Connor. It was published in 1995 by Emerald City Press, an imprint of Books of Wonder devoted to new Oz books.
As the story opens, Bungle confesses her boredom with her current routine. Trot suggests that the Cat try to make herself useful to others, as a major innovation in her life. The Cat is bored enough to give it a try.
Princess Ozma and friends are planning a party to celebrate the 75th anniversary of Betsy Bobbin's arrival in Oz. Betsy wants to invite Ann Soforth and other old friends from Oogaboo to attend; Bungle volunteers to convey Ozma's invitation, and heads for that remote corner of Oz.
Meanwhile, a gang of young delinquents called the Bad Lads is launching a planned takeover of Oogaboo. They are originally from the southwestern corner of Oz, but their home stomping grounds have become unwelcoming: the giant Herku have been dipping Bad Lads into the Truth Pond, and it's hard to be a real delinquent when you can't even lie. So a group of 26 Bad Lads have targetted Oogaboo; in addition to its isolation, the Lads are attracted to its gun tree.
Once Bungle learns of the Bad Lads' threat, she races back to the Emerald City to inform Ozma. The Girl Ruler organizes a party to aid the Oogabooans, with the curious composition of Cap'n Bill, Trot, Button-Bright, the Hungry Tiger, and Bungle. Ozma equips the party with magical amulets to protect them from bullets, plus a magic tent, an inexhaustible lunchbasket, and other supplies, and sends them to save the day.
These events are witnessed by two young visitors from the United States. Barry and Becky Klein are 12-year-old orphans from California. Barry finds and old bottle on a beach, and opens it to release a genie and earn himself three wishes. He uses his three wishes to take his sister and himself to Oz (that's two), and learn the secret of working transformations by a magic word (that's the third). Once in Oz, the two children get around by transforming each other into a range of creatures — falcons, sparrows, wood ducks, river dolphins, hawks, and goldfinches. As sparrows, they eavesdrop on Ozma's court, and hear of the mission to Oogaboo. They decide to tag along: if they render useful service, perhaps Ozma will invite them to stay in Oz permanently.
The children follow the rescuers; they are eventually caught by Bungle, and confess their plan. Cap'n Bill and the others accept their company, and the children prove useful in defeating the Bad Lads and restoring Oogaboo to its citizens.
The Bad Lads are sentenced to a dip in the Truth Pond. Ozma finds Barry and Becky worthy of residence in Oz; and she promotes Bungle to Principal Investigator to the Throne — an honor that leaves the Cat momentarily speechless.
Hulan depends heavily on Baum's eighth Oz book, Tik-Tok of Oz, as a model and inspiration for his work. He uses alliterative and assonant chapter headings, as Baum did, and employs several of the characters of the earlier book. He also borrows the magic word Pyrzqxgl from Baum's The Magic of Oz.
Hulan makes a point of setting his story contemporaneously: if Betsy Bobbin is assumed to have arrived in Oz in 1914 (the publication date of the novel in which she debuted), 75 years later would set The Glass Cat of Oz in 1989. Other modern Oz authors take a similar approach: Eric Shanower sets his The Giant Garden of Oz in the late twentieth century, "eighty-some years" after events in Baum's originals. (Some Oz fans have developed complex chronologies for the Oz mythos, dating the fictional events in the books of Baum and other authors to the real-world calendar.)
Guns in Oz
Firearms are not usually thought of in the context of Oz, and they are rare in that fairyland. Yet they are not entirely absent: the army of Oz carries a musket, though it is usually not loaded. The main source of guns in Oz, as far as is known, is the gun tree that grows in Oogaboo, along with a variety of other exotic-fruit-bearing trees.
Ozians cannot be killed by gunfire; the enchantment that rules Oz will preserve their lives. They can be severely injured, however, so that gunshot wounds are to be avoided.
Magical transformation in Hulan's book follows the precedents in Baum's works. Barry and Becky cleverly transform each other rather than themselves, and at one point avoid disaster by doing so. When switching from air to river transit, Barry has his sister turn him into a pike — but then finds that he cannot pronounce the magic word effectively; the pike's jaw is not quite right for the task. The children learn from their mistake, and change into dolphins instead.