Nothing is harder to isolate than the uncertain, unstable chemistry of a McGuane novel (The Sporting Club; The Bushwhacked Piano) catalyzed by great humor and a latent if everpresent violence. Ninety-Two in the Shade, flashing with just that kind of intensity, is set in the Florida keys where young Tom Skelton who ""required a sense of mortality"" has gotten his shaky self together to the point of deciding that he wants to become a fishing guide although the territory is well staked out by two others, one of whom has openly declared he will kill him. But then it's the only thing he can do ""half right."" If Tom is a maverick, he comes by it honestly; his grandfather, an entrepreneur-manipulator, is a ""crook of limitless cynicism"" while his father has recently holed up in the bed, only to emerge at night. But Tom has his own limited field of vision: ""It's just that when you realize that everyone dies you become a terrible kind of purist."" And even where McGuane's novels are loosely structured (filled with surprising to startling moments) you read this in the expectation of what will, what must, happen. There's one great shaggy big fish story and you won't need to be reminded that this is Hemingway country, with a vast metaphysical difference. McGuane is very much his own man stalking his own kind of truth, and part of the inordinate vitality of the novel derives from the fact that life and death are the same process. A talent hard to define or confine -- it just is.