A lavish photo-and-text celebration of everyone's favorite dinosaur. Although paleontologist Horner and science-writer Lessem (Kings of Creation, 1992, etc.) join forces here (as they did on the children's book Digging Up Tyrannosaurus Rex, 1992), this is presented as a first-person account by Horner, covering both his years as a fossil hound and current scientific understanding of T. rex. The authors unfortunately strike an off-the-cuff pose that resembles that of an overeager high-school science teacher: ``We're lucky to have the opportunity to know T. rex, study it, imagine it, and let it scare us. Most of all, we're lucky T. rex is dead. And we're not.'' The new discoveries they trumpet will thrill only the most avid T. rex-philes: that the dinosaur was leaner and more birdlike than previously believed, perhaps a scavenger, with a variable body temperature. But underneath this hype lies a fine popular history of T. rex research, from the earliest discoveries to the most recent find, a nearly complete specimen now sitting in FBI lockup while ownership is sorted out in the courts. With infinite patience, Horner walks us through the tricky stages of excavating and reconstructing a T. rex fossil; details of tyrannosaur anatomy; and ideas about how the beast survived in the ecology of the Cretaceous period. In a science dominated by flamboyant figures, Horner's cool head is notable: Citing the inadequacies of data, he refuses to rule on whether T. rex had depth vision or hunted in packs or cared for its young. Moreover, his few strong opinions are unusually independent: He rejects the popular theory that an asteroid-strike killed off the dinosaurs, and he rails against mounted dinosaur skeletons as misleading—and too expensive. Aggravatingly juvenile at times, but stuffed with T. rex goodies and well-positioned to enjoy some of the run-off from Steven Spielberg's upcoming dino-megaepic, Jurassic Park. (Illustrations—eight pp. color & 72 pp. b&w—and line drawings— not seen)