John Knowles's first book, "A Separate Peace," was one of those legendary adolescent novels, passed hand to hand around the dormitories at Groton, buoyed into successive paperback editions by that most valuable of commercial assets, an underground reputation. It was a very special book, about a special type of Eastern prep-school kid, and it was notable for two qualities: a complete absence of humor and a curious air of self-seriousness, as if it had been composed in the service of a 16-year-old boy's romantic self-image. "A Separate Peace" was a schoolboy tragedy seen entirely in schoolboy's terms. Its protagonist was the classic prep-school hero, a sort of eccentric Hobie Baker, innocent, straight, the victim of someone else's destructive complexity. For all its tragedy and blood-guilt, Knowles's first novel was squarely in the tradition of Dink Stover and the Boys Own Paper. Like many cult books, its success derived...