After author David Foster Wallace committed suicide last September, his longtime agent, Bonnie Nadell, found herself lost in a maze of words. Scattered on two different computers and in hard copies stashed around the cluttered garage where Mr. Foster Wallace had worked in Claremont, Calif., she discovered multiple versions of his final, unfinished novel. She had no idea which draft he preferred. Mr. Wallace's novel about I.R.S. agents, due out next fall, is being assembled based on the author's notes. "A great deal of it is a puzzle," she said of the novel, titled "Pale King."

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