The return of beloved, triumphant, driven, haunted, playacting, social-reforming Boz--that most biographable of writers. With so many anecdotes, personalities, projects, and psychological ramifications in the picture from Pickwick to Drood (the Edgar Johnson biography stretches through two hefty volumes without padding or blather), a short study, like this pleasant, balanced one from Wolf Mankowitz, can only suggest. But Mankowitz suggests well, declining to investigate each path himself but always opening the fan of possibilities. Dickens' ambivalent relationships with his parents, his sisters-in-law, his children, wife, and mistress(?)--all are unsurreptitiously hinted at even while Mankowitz engagingly handles the sheer narrative bulk of business dealings (emphasizing the ""steel blade of will""), American tours, Italian travels, Macaulay-Macready-Thackeray camaraderie, amateur theatricals, and. . . the books themselves. Here Mankowitz is weakest, gamely endeavoring--in one or two paragraphs--to sum up a novel and relate it to the life-and-times, but an occasional inspired phrasing (Little Dorrit's central image: ""an interminable, Piranesian prison"") almost redeems a clutch of oversimplifications. Though certainly not shaped in any dramatic way that would lend sense to the announcement that it's ""To be shown on Masterpiece Theatre beginning August 28th,"" Dickens of London is literate, humane, and knows its place, which is all--especially when abetted by a truly Dickensian bounty of illustrations--that a popular biography of the ever-surprising Boz needs to succeed.