Roger Ebert, the only film critic with a star on the Hollywood Walk of Fame, has written more than a dozen books about movies. He has also written one about “the mystery and romance of the rice cooker.” And he presides over what may be the most industrious blog in all of moviedom, rogerebert.com, which is packed with news, reviews and so much savvy miscellany that it has attracted a very large following.Interest in the site should spike higher on the strength of “Life Itself,” Mr. Ebert’s candid, funny and kaleidoscopic new memoir. This is the best thing Mr. Ebert has ever written. It will surprise even those already familiar with his huge body of work (no pun intended, although Mr. Ebert’s erstwhile struggle with his Michelin Man body image is one of the topics that “Life Itself” takes on). And although Mr. Ebert can no longer eat or speak, for reasons that the book explains, he has grown better than ever at replaying “the jokes, gossip, laughs, arguments and memories I miss.” The book sparkles with his new, improvisatory, written version of dinner-party conversation.When health problems and radical facial surgery took away his voice in 2006, Mr. Ebert turned to blogging as a substitute. That transition clearly influences this book. “Life Itself” is made up of short chapters that have the vitality of blog entries without the sloppiness that often goes with them. This format may seem superficial, but the book actually honors Mr. Ebert’s deep affinity with Thomas Wolfe. He shares Wolfe’s love affair with memory and passionate hunger for experience without Wolfe’s windy verbosity — or Wolfe’s way, as Mr. Ebert puts it, of “uttering wild goat cries to the moon.”The first, heavily nostalgic part of “Life Itself” is full of references that many readers will not recognize. At 69, he is old enough to remember Lash LaRue on the movie screen and “Our Gal Sunday” on the radio. He is committed to replaying these memories, but they are eclipsed by a portrait of the author as an ambitious young man. As a boy in the university town of Urbana, Ill., he ran what he called the Roger Ebert Stamp Company. By high school he had a yen for journalism and treasured another kind of stamp: a “by Roger Ebert” stamp pad. And at 25 he was the film critic for The Chicago Sun-Times, at the time of “Bonnie and Clyde” and “The Graduate,” with Pauline Kael about to arrive at The New Yorker. “It was a honey of a job to have at that age,” he writes.The middle part of the book devotes attention to movies. It devotes even more to Mr. Ebert’s early dealings with famous actors and filmmakers. He devised and perfected an interviewing technique very unlike the first-person approach that prevails today. He kept himself out of his stories and let his subjects talk. Mr. Ebert’s ear for a good story, riotously illustrated by his pieces on Lee Marvin and Robert Mitchum, is apparent throughout this book. He immortalizes his civilian friends as if they were movie stars too.Mr. Ebert writes about how his alcoholism shaped some of these good times. Too hung over to interview Sophia Loren, he turned the job over to his very Irish friend John McHugh, who claimed that each time his parents sent him to see “How Green Was My Valley,” he had a new brother nine months later. “Miss Loren, is that a tiara you’re sportin’?” he quotes Mr. McHugh as having asked, interviewer style. These wild times were funny until, for Mr. Ebert, they weren’t. With the help of Alcoholics Anonymous he stopped drinking in 1979.“Did I know drinking made me unmarriageable,” Mr. Ebert asks now, “or did I simply put drinking ahead of marriage?” He is ready to ask himself such questions because, he says, “I will write this book only once and might as well not make it fiction.” So this book is as revealing about Mr. Ebert’s physical experiences as it is about other aspects of his life. An early encounter in the front seat of his father’s ’55 Ford: “My hands strayed to her netherlands. My own movables were rummaged.”Mr. Ebert writes with deep love about his marriage to the former Chaz Hammelsmith, whose family background could not be more different from his own. He is of Irish, Dutch and German descent, and he had an Aunt Mame. His wife is African-American with a mother known as Big Mama, and a big, affectionate group of relatives who turned Mr. Ebert into an instant father and then grandfather relatively late in life. He writes frankly about his gratitude. “She continues to make my life possible, and her presence fills me with love and a deep security,” the book says. “That’s what a marriage is for. Now I know.”Before they married, Mr. Ebert told Chaz that he had had a salivary tumor removed in 1988. He had ignored it even though it was visible in a photograph of him with Gene Siskel, with whom he created the prototype for dueling critics as television stars. (Mr. Siskel died in 1999.) Mr. Ebert’s cancer was rare enough to wind up on the cover of the Walter Reed military hospital’s research magazine. But, he says wryly, “it was the kind of publicity difficult to turn into Nielsen ratings.” Suggesting that radiation treatments given to him in childhood to help ear infections may have caused his illness, he writes, “Because I was born four or five years earlier than most of the boomers, I was the canary in their coal mine.”As “Life Itself” moves toward an account of this and later punishing medical ordeals (including thyroid cancer, facial bone loss and failed reconstructive surgery), Mr. Ebert writes as if it were a matter of life and death, because it is. He is well aware that it will some day serve as his valedictory. But he is alert to the way others perceive his health, and he wants to correct misconceptions. No hand-wringing please. No confusing a disfiguring ordeal with a prognosis. And no flinching. “You don’t like it, that’s your problem,” he says about his greatly changed, though still remarkably cheery, face. “I’m happy I don’t look worse.” When Esquire ran the huge close-up that revealed his new appearance to the world, Mr. Ebert hated not only the intimations of doom but also that his hair had been so carefully combed.“Life Itself” is the best possible antidote to his experience of loss. It communicates a whole lot of gusto and very little grief. Its globe-trotting, indefatigable author comes across as the life of a lifelong party. “I may seem tragic to you, but I seem fortunate to myself,” he writes. “Don’t lose any sleep over me.”