It's true that no big, balanced Maugham bio has emerged since his dirty linen started being aired about 15 years ago (largely by catty nephew Robin)--so this behemoth fills an arguable vacuum. But it does little more than that; Morgan (On Becoming American) mostly just tells all, chattily, bringing little shape to a sad, glamorous, but finally flat life-story. He's best on the early years: Willie was a carefree 1880s tot, but at age eight his mother died, leaving him ""a permanently deprived child"" who'd always connect love with suffering, who'd see all women as betrayers. He developed a stammer and homosexual yens (""for boys who had the qualities he lacked"") but felt the need to keep his sex secret; as medical student and fledgling novelist, he became an Edwardian prototype, ""a facade person"" who took mistresses while knowing ""in his heart he was homosexual."" Fame came only after plodding, minor success in fiction--with a string of slick London stage hits. And fortune (carefully hoarded) came too, permitting WSM to roam the world, with alcoholic lover-secretary-procurer Gerald Haxton, in pursuit of story ideas, artwork, and boys--a lifestyle undisturbed by marriage to pregnant mistress Syrie, whom WSM came to divorce and loathe. By the '30s, he was the Grand Old Man of Letters, moving to the Riviera, where he'd grow nastier, richer, and ever more a wretched dirty-old-man. Morgan rebuts only a few specks of Robin Maugham's dirt and doesn't downplay WSM's foulness; nor do his sturdy work-by-work critiques make great claims--Cakes and Ale, Of Human Bondage, and a few stories aside. (""What one misses . . . is surrender to the muse; he is always holding back."") What remains is impressive research, myriad anecdotes (some irrelevant, some--like WSM's dabbling in espionage--intriguing), and a grim little case history at the center . . . all of which lapse, in the final 300 pages, into a dull recital of houseguests and miseries. The Maugham bio--hands down--but neither momentous nor consistently absorbing.