Over the past two decades, few writers have charmed as many critics and readers as the British novelist Ian McEwan. He is probably best known for his 2001 novel Atonement, which sold over 4 million copies and was turned into a popular movie, but McEwan has been selling books and winning awards since the mid-1970s. Before Atonement, there was The Comfort of Strangers, Black Dogs, Enduring Love, and Amsterdam; and since Atonement, he has published two more successful books: Saturday and the novella On Chesil Beach.

McEwan has won both the National Book Award and the coveted Booker Prize. He's been informally dubbed Britain's National Author and, by royal decree, Commander of the British Empire.

Several things account for the McEwan phenomenon. The fine, elegant thread of his language is easy and pleasurable to follow. His authorial voice is genial, direct, and refreshingly free of modernist irony. Novelists such as John Updike and Philip Roth, both of whom McEwan has written about admiringly, often tinge their characterizations with irony to avoid sentimentality. But when McEwan presents a character, he is never winking at the reader. He recently acknowledged that a “certain ironical tone” he developed for his forthcoming novel was hard for him to come by. McEwan's narrative directness is at least superficially similar to that of romance and adventure fiction, where characters usually appear in plain aspect.

The plots of McEwan's literary fiction also have much in common with those typical of popular fiction. The “ripping good yarns” of bestsellers liberate readers from what McEwan calls the “dead hand of modernity.” He laments that literary modernism sometimes smothers narrative by focusing entirely on character instead, leaving readers with little or no momentum to pull them along. His own novels are page-turners. Irony, while mostly absent from his tone and characterizations, is abundant in his plots. They teem with suspense, surprise, and twists of fate. To create narrative tension, McEwan often deploys a violent incident or a threat of violence. His earliest writing earned him the nickname “Ian Macabre.”

In other ways, though, McEwan is very much within the main current of modern literary fiction. His books are as full of psychological observation as they are of incident. He often cites as a defining influence Virginia Woolf and her free, indirect style—a dazzling articulation of consciousness that traces the subtlest motions of her characters' minds. McEwan pays tribute to Woolf both in and by his own writing. Like Woolf's Mrs. Dalloway, McEwan's 2005 novel Saturday describes a single day in the life of a Londoner. But Saturday's main debt is not to other novels, but to science and the culture of science-and to a particularly aggressive kind of scientism.

Of the six novels McEwan has published in the past twenty years, three have been vehicles of a movement that has grown in strength and numbers over the same period: the so-called New Atheism, which fortifies traditional skepticism with the findings of the natural sciences, especially astrophysics and biology. What is perhaps newest about the New Atheism is its missionary zeal—it is not just an esoteric wisdom for the elite but good news for the masses, whom it evangelizes with billboards, documentary films, summer camps for kids, and “de-baptisms” for adults. But the most efficient carrier of a message is still a good story.

McEwan himself was drawn into the New Atheist fold by degrees. He emerged from the 1960s with a vague mystical curiosity, but with his divorce from his first wife, a New Age writer, his curiosity gave way to skepticism. Wanting to “shake off post-hippie junk,” he turned to Freud, whose thought shapes the orientation of McEwan's earliest fiction. Later, he turned more and more to Darwin, who provides the metanarrative for his later work. In the 1980s, McEwan became part of a “Friday Lunch” group that included Christopher Hitchens, a fellow word-man with whom he developed a lasting friendship and who would go on to become one of New Atheism's most recognizable celebrities. Hitchens has said that McEwan showed signs of “the zeal of the convert.” By the early 1990s, McEwan could no longer settle for the vague aura of irreligion his novels shared with much contemporary fiction. The result was his 1992 novel Black Dogs, a kind of dramatized Platonic dialogue between rationalism and faith, which the protagonist describes as “the twin poles along whose slippery axis my own unbelief slithers and never comes to rest.”

Unbelief, however, came fully to rest a few years later with McEwan's best-selling 1997 novel Enduring Love, an allegory in which atheist rationality prevails against intuition, New Age spirituality, and deranged Christian zeal. “It is not for nothing,” McEwan would later write, “that one of the symptoms in a developing psychosis, noted and described by psychiatrists, is religiosity.” Enduring Love and Black Dogs both testify to McEwan's growing conviction that religious faith is “at best morally neutral, and at worst a vile mental distortion.”

It is possible to read these two books as parts of a trilogy that would be completed by Saturday, a story not of ideas only, like the other two novels, but of an ideal. It offers readers a day in the life of a New Atheist Everyman. Long before he wrote Saturday, McEwan had added to his inner circle the seminal figure of the New Atheism, the science writer Richard Dawkins. Humanity's happy future, Dawkins insists, is a world guided by science and liberated from the scourge of religion. Saturday can be read as a narrative encapsulation of this creed.

What gives Saturday its evangelizing force is its use of the icon, the embodied ideal, rather than argumentation. Argument speaks to the mind, but icons reach into our imagination. It is there that McEwan hopes to plant Saturday's hero, Henry Perowne. The reader accompanies Henry as he lives out what appears to be a life of blessings in a universe without God. We watch how the authentic atheist feels, muses, loves, grieves, and exults. Ecce homo: here the man is the message.

Henry's family and children live happily without a single artifact of God or the gods. Henry himself is a man of integrity and constant good cheer, a world-class neurosurgeon, a loving parent. He craves intimacy with his wife like a newly­wed. “When he thinks of sex, he thinks of her.” His wife Rosalind, a distinguished lawyer, is kind, intelligent, and loving, a supportive mother and an enthusiastic partner in the nuptial bed. In the morning Henry loves to lie in the “ruined, pornographic” rumple of its sheets and listen to Rosalind sing hymns as she prepares for her day—not Christian hymns, but snippets from On the Origin of Species. Darwin's phrase “There's grandeur in this view of life” is one of her favorite songs—one of Henry's too.

The Perownes have two bright and devoted children. Their daughter Daisy is a chirpy college graduate and aspiring poet. She is tight with her younger brother, Theo, who is described as a member of the first “sincerely godless generation.” No one in Theo's “bright, plate-glass, forward-looking school ever asked him to pray, or sing an impenetrable cheery hymn.” Henry is glad his son is free of the old religious anxieties: “there is no entity for him to doubt.” Like many teenage boys, Theo loves music and plays in a local band. But his edgy, bluesy songs don't bristle with the usual discontents of youth. They are lyrics of uplift and hope. As Henry watches his son perform a song with his band, he catches a “glimpse of what we might be, of our best selves, and of an impossible world in which you give everything you have to others, but lose nothing of yourself.” The song begins: “Baby, you can choose despair / or you can be happy if you dare.”

But this domestic idyll is still hedged with the doubts and dangers of the outside world. McEwan begins Saturday on an ominous note. Soon after rising on Saturday morning, Henry looks out a window of his London home and sees an airplane moving low over the city, one of its wings apparently on fire. The sight evokes the nightmare of 9/11, still fresh in Henry's memory, with England now on the brink of the Second Gulf War and demonstrators rallying this very Saturday against the invasion of Iraq. To increase the torque, McEwan reveals nothing more of the plane's fate for nearly two hundred pages. Henry eventually learns that the plane's cargo fire was safely extinguished after a smooth landing, but McEwan uses the specter of the burning aircraft to jumpstart Henry's thoughts on God and religion, thoughts that continue throughout the day. For McEwan, and for the New Atheists as a group, religion is what 9/11 is all about. The events of that day delivered historic proof of the madness and “vile mental distortion” of belief in the supernatural.

A plane crash might be caused, Henry speculates, by “a man of sound faith with a bomb in the heel of his shoe.” But on board there will also be others praying “to their own god for intercession. And if there are to be deaths, the very god who ordained them will soon be funereally petitioned for comfort.” The absurd “babel of various gods” takes Henry back to his school days, when a bus accident involving the deaths of 116 children caused him to suspect “that the kindly child-loving God extolled by his headmistress might not exist.” As he got older, “most major world events suggested the same.” For Henry, religious faith involves a “simple anthropic principle.” He sees the “primitive thinking of the supernaturally inclined” as “an inability to contemplate your own unimportance” and as “a childish evasion of the difficulties and wonders of the real.”

Like McEwan himself, Henry is convinced that faith inhabits the spectrum “at whose far end, rearing like an abandoned temple, lies psychosis.” He muses on the Falun Gong's belief in a miniaturized universe rotating in the practitioner's abdomen. He thinks of Muslim women in their black burkas (“like kids larking about on Halloween”) and of Christians preaching a God who sent us an actual child. “The last thing we needed” on this “spinning rock already swarming with orphans,” Henry decides.

His own cosmology is founded on Darwin's masterwork—especially its later editions, where Darwin “ditched” any mention of a creator. From Darwin's writings “only one conclusion” can be drawn, Henry says: that “exalted beings like ourselves” arise “from war of nature, famine, and death.” This is what Henry's wife sings about in the morning. “This is the grandeur,” Henry explains, and “a bracing kind of consolation in the brief privilege of consciousness.” How to account for the persistence of religious faith? Henry concludes that the whole business is an evolutionary survival tactic: “Over time, down through the generations, this may have been the most efficient: just in case, believe.”

But if faith is just an impulse to believe, it is one to which Henry himself seems not to be immune. He predicts with certainty that “the brain's fundamental secret will be laid open one day.” For him science is the way to truth; through science alone “the journey will be completed. Henry's sure of it.... That's the only kind of faith he has.” Or, to use his own expression, Henry has faith and goes on believing. Henry's scientism demands an assent of the will, a leap, like any religion. And he is not above expressing his own kind of religious rapture. There is, he says, no more exciting “creation myth” than evolution:

An unimaginable sweep of time, numberless generations spawning by infinitesimal steps complex living beauty out of inert matter, driven on by the blind furies of random mutation, natural selection, and environmental change, with the tragedy of forms continually dying, and lately the wonder of minds emerging and with them morality, love, art, cities-and the unprecedented bonus of this story happening to be demonstrably true.

His daughter thinks “demonstrably true” has the ring of old-time religion, but then it is something very close to old-time religion that Henry seems to have adopted. One might think that the “blind furies” of cosmic randomness could trigger existential malaise. On the contrary. Once, in England's Lake District, Henry experienced a “leap of gratitude for a glimpse, beyond the earthly frame, of the truly impersonal.” For him, the “random ordering of the world, the unimaginable odds against any particular condition” is a source of elation. Even as a child “he never believed in fate or providence, or the future being made by someone in the sky. Instead, at every instant, a trillion trillion possible futures; the pickiness of pure chance and physical laws seemed like freedom from the scheming of a gloomy god.”

It might be hard for other people to draw such consolation from “the truly impersonal”; but even as true believers go, Henry is extraordinarily impervious to doubt. Indeed, he seems marvelously unbothered by the difficulties of mind and mood that beset most adults, whether atheists or believers. Even Christopher Hitchens confesses to having his own dark nights, when he feels the lure of belief. Hitchens considers this lure to be evolution's deadliest flaw, and writes of having to oppose innate yearnings for a supreme being with all his powers of mind. No such yearnings afflict Henry.

Of the four gifts of the universe in Henry's private creation myth—morality, love, art, cities—it's morality that presents the biggest challenge to a cosmology of pure chance. Morality is a sensitive subject to old and new atheist alike because of the danger Dostoyevsky famously warned of—that “without God anything is possible.” But everything about Henry's behavior in Saturday seems to tell against this conclusion. The key to successful moral action, the pragmatic Henry tells us, “is to be selective in your mercies. For all the discerning talk, it's the close at hand, the visible that exerts the overpowering force.”

In a bravura plot move that does for the second half of the novel what the flaming plane does for the first, McEwan illustrates Henry's ethic of proximity with a scene that's pure Ian Macabre: a brutish thug threatening a naked young woman with a knife. The young woman is Henry's daughter, Daisy. The thug is Baxter, who has broken into Henry's house after stalking him for much of the day. The family watches in horror as he forces Daisy to strip. But Henry and Theo rush at Baxter, and at the end of a violent struggle, the intruder falls and fractures his skull. Later that night in the hospital, Henry himself operates on Baxter. In the recovery room, he takes Baxter's pulse, his hand lingering on the patient's wrist longer than it has to. Henry offers solace to this man who seemed about to rape his daughter. Not only does Henry's ethic of good will and charity hold firm, in the end he exhibits a compassion for Baxter that is positively Christlike.

This whole episode invites an obvious question: How do Henry's moral imperatives relate to, or derive from, the blind furies of chance? How can they be binding if they claim as their only basis a freak agitation of atoms? In what almost appears to be a hijacking of ancient Christian doctrine, Henry implicitly hints at a kind of serendipitous natural law, one that obscurely descends from inert matter. Henry is convinced there's “a morality, an ethics down among the enzymes and amino acids,” but we'll find it only when we stop “looking in the other direction.” There is even for Henry a “modern variant of a soul” to be found “in the codes of his being, his genotype.” Henry's truly impersonal universe seems to generate the same intelligible moral code as the universe of the truly personal, only without the superstition that spawns intolerance and impenetrable cheery hymns.

For Henry, the legacy of cosmic accident extends to everything from London to logic to love. Saturday concludes by affirming this “pickiness” of cosmic accident, a legacy that extends, against a “trillion trillion”-to-one odds, to love. It is a love that does not pretend to transcend the material world, but human possibility is all Henry asks for. At the close of his long Saturday, Henry cuddles up to his sleeping wife's “silk pyjamas, her scent, her warmth, her beloved form.” The novel ends with this scene. As Henry finally dozes off, his mind lands softly on its one true comfort. “There's always this, is one of his remaining thoughts. And then: there's only this.”

So, what are we to make of the good news according to McEwan? He presents it with the full arsenal of his skills: a direct and elegant style, an instinct for bracing narrative, a Woolfian mastery of his characters' interior life, and technical descriptions (of surgery, for example) that achieve a poetry all their own. Saturday abounds with purely literary pleasures.

Underneath the sophistication of technique, however, McEwan's accessible, irony-free characterizations turn simplistic or, worse, sentimental. The Perownes are an impossibly happy family, and Henry himself is so likable, so accomplished, so without flaws or angst, that he seems less a person than a secular emblem. His bubbly enthusiasm for cosmological randomness is implausible and unintentionally amusing, while his brash scientism rings with a fundamentalist fervor he would find unseemly in religious believers. Much as we may enjoy his pleasures and adventures, it's a struggle to take this Atheist Everyman as seriously as the author seems to take him. McEwan's hallmark plot manipulations, achieved with exquisite showmanship, are here brazenly pressed into the service of an ideology. The fiery aircraft casting the lurid pall of 9/11 over Henry's morning becomes a reductive metaphor for the irrationality of religious faith. The carefully staged Baxter episode is brandished as evidence that altruism is possible in a pure-chance universe.

In 2005, Saturday won the James Tait Black Memorial Prize from the University of Edinburgh, one of the most prestigious awards for literature in the English-speaking world. It puts Ian McEwan in the company of D. H. Lawrence, Graham Greene, and Evelyn Waugh. That certainly tells us something about McEwan's literary stature. But it tells us more, perhaps, about the appetites of our literary culture. The satisfactions of genre fiction are now OK in serious fiction; and so, alas, are heavy-handed homilies—as long they promote the right gospel.