Like all the best comic writers, Smith is dead serious. She's got things to say about some big questions, and not just the politically trendy ones that the multicultural nature of her cast of characters might suggest. In the novel's opening scene, it's 1975 and 47-year-old Archibald, worn out and hopeless after a divorce from a mad Italian named Ophelia, decides to gas himself in his car on a street in Cricklewood. His plan is thwarted when an irate hallal butcher -- alerted by his son, who'd come out to clean pigeon crap from the shop window -- demands that Archie get his car out of the delivery zone. "If you're going to die round here, my friend, I'm afraid you've got to be thoroughly bled first," the butcher tells him.

From this initial shot of high-octane gallows humor, "White Teeth" is life-affirming in a thoroughly unsentimental way. "Although he was not one of her better specimens, Life wanted Archie," Smith writes, "and Archie, much to his own surprise, wanted Life." And we're off.

Elated and unburdened, Archie ends up at a free-love party, where he's knocked out by his first glimpse of the beautiful, 17-year-old Clara, "black as ebony and crushed sable," her one physical flaw a missing set of front teeth, courtesy of a mishap on Ryan Biggs' Vespa. Clara, for her part, is keen to escape the Jehovah's Witness hell of her mother's house.

Within six weeks this unlikely pair is married. But what pair of people isn't unlikely, when you get right down to it? We're all the products of coincidence, of alliances born of hopelessly mixed motives. With its hilariously winding plot lines and vividly drawn, almost Dickensian characters, "White Teeth" reminds us that while all bonds between human beings have an element of randomness, the wonder is that quite often, for one reason or another, they actually hold.

The friendship of Archie and Samad, forged inside a stifling five-man tank during the final weeks of World War II, couldn't be more improbable: The fast-talking Samad is a handsome, boastful, educated Bengali determined to grab some glory despite his lowly rank and the indignities of his assignment to the tank unit; Archie is a practical-minded, good-natured, unremarkable lad from Brighton City. And yet their relationship anchors the two men when they find each other again decades later in London. Both now middle-aged, their personalities are just as distinct even after three decades of disappointments and frustrations.

Smith creates equally compelling characters in the two men's much younger wives, Clara and Alsana, who become pregnant at the same time (Clara with Irie, Alsana with twin boys, Millat and Magid) and strike up a wary friendship. Clara turns out to be curious, sweet-natured and slightly timid, while Alsana is shrewd and fierce, far from the easy bargain Samad assumed her to be when their marriage was arranged.

"By Allah, I will always give as good as I get," Alsana yells when her niece tries to talk her into a Western approach to her marital difficulties. "The truth is, for a marriage to survive, you don't need all this talk, talk, talk, all this 'I am like this' and 'I am really like this' like in the papers." Is it surprising that Clara and Archie's sincere, self-doubting daughter, Irie, develops a desperate, pining love for the smooth, thoughtless Millat? You could call it arbitrary, or you could just call it life.

Alsana's view of the English -- they're "the only people who want to teach you and steal from you at the same time" -- owes something to her amusingly jaundiced eye, but it also captures the inevitable push-pull, the love-hate between the immigrants and the native British in "White Teeth." As we learn that an Englishman seduced Irie's Jamaican great-grandmother, leaving her pregnant with Hortense, Smith comments in an aside, "oh, he loves her; just as the English loved India and Africa and Ireland; it is the love that is the problem, people treat their lovers badly."

Irie's and Millat's search for roots -- the novel's central metaphor and the source of its title -- both preoccupies and paralyzes them. They crave the same kind of family information that, instinctively, they'd rather not know; the political crimes and dislocations and personal tragedies that led to their English births are not pretty.

Maya Angelou reads from "The Heart of a Woman"