Fantasy set in the universe Duane created in a YA series (Deep Wizardry, 1990, etc.). Cats are intelligent and have their own language, Ailurin; feline wizards with their human counterparts keep transit gates open and the world safe from disasters and invasions. Three New York wizards, house pet Rhiow, neurotic Saash, and dumpster resident Urruah, are detailed by the Powers That Be to repair a malfunctioning gate beneath Grand Central Station before a train accidentally gets hurled into another dimension. In the train tunnel the three battle hordes of rats and rescue a kitten, Arhu, who, though resentful and hostile, is destined to become a wizard, too. Next, the trio must travel into an alternate world of the past, Downside, to locate the gate's power source--but the locals are dinosaurs, and very belligerent. Then the investigators' human Area Advisory vanishes; they discover a magic spell written in Ailurin on an ancient Egyptian papyrus; Arhu develops a talent for seeing the future; and it becomes clear that they're being opposed by a dinosaur wizard backed by the evil Lone Power. Often intriguing, with a well-worked backdrop, but it's hard to find a logical or emotional connection between cats and dinosaurs. Still, fantasy-loving ailurophiles will curl up and purr.