Oryx and Crake by Margaret Atwood

The Canadian visionary has gone back to the future with an irresistible tale of techno-tyranny and human rebellion. Lisa Appignanesi is chilled and thrilled

The best future fictions are deeply embedded in the present. They prod our existing fears into the light and build a dystopic world on them. So the monsters haunting 1948 – both Nazi and Stalinist – were incarnated in Orwell's Nineteen Eighty-Four, with its ever-vigilant Big Brother, its thought police, its daily two minutes of hate and its newspeak, which enshrined "doublethink": War is Peace, Freedom is Slavery, Ignorance is Strength.

Writing in 1984, Margaret Atwood gave Orwell's future an update. The Handmaid's Tale inflected the basic totalitarian police state with current, feminist anxieties. The fundamentalist right was on the rise. Its disciplinary puritanism, its biblical literalness, its view of woman as a walking womb, are the cornerstones of Atwood's theocratic state of Gilead. In a post-nuclear world where conception is difficult and children scarce, the "haves" can bring in a caste of "have-not" handmaids to do the bearing for them, in the manner of barren Rachel and patriarch Jacob.

Now, five major novels later, including the Booker- winning The Blind Assassin (which contains its own pastiche dystopia), Atwood has gone back to the future. It's a future which has changed as much as our present has. Once again, it's prescient. And it's scary.

Oryx and Crake begins on a strip of white beach in a time after. On the vacant face of Snowman's watch, it is Zero Hour. He may be the sole human survivor of an as yet unnamed apocalypse.

He is naked, but for a grubby sheet. It is very hot. He lives in a tree, unreachable by the wild wolvogs, pigoons, and rakunks. Food is scarce and must be scavenged for. Half bits of quotations from mantras or handbooks fall into his mind. "There are a lot of blank spaces in his stub of a brain, where memory used to be."

The filling-in of those blank spaces is what the past time of the book is about. It is our present, with certain features writ large. Atwood's spirit here is energetically Swiftian. As her opening quote from Gulliver's Travels suggests, she is "relating plain matter of fact"; seeking to inform.

The world has warmed. The coastal aquifers have turned salty, the northern permafrost melted, the Asian steppes have become dunes, lakes have shrunk to reeking puddle size. Sea levels on the east coast have risen so quickly that beaches have been washed away, together with a few coastal cities.

Given the weather, everything is ersatz – spliced, engineered, cloned – or gone. Politically, the globe is in ever-shifting turmoil. North America is divided between rich, policed, gated communities and "pleeblands" – the teeming, unruly remains of the big cities inhabited by those who mostly already inhabit them. Capitalism is rampant.

Made in the image of Microsoft, the privileged gated communities, patrolled by guards, belong to vast biotech corporations. Like states, they compete, have spies who steal from other companies or try to undermine them, allow no internal dissent, are interested only in profit. During Snowman's childhood, they also incarnate an idea of the good life which comes out of a Fifties suburban dream: security, schooling, sodas and shopping, with mom at home and dad at Biotech.

Snowman begins life as Jimmy at OrganInc, the corporate community dedicated to the pigoon project. His father is a leading "genographer" whose goal it is "to grow an assortment of foolproof human tissue organs in a transgenic knockout pig host". He moves on to the bigger HelthWyzer compound, where he works on replacement "Nooskins".

Though the projects might be successful, the marriage is not. Jimmy's mother becomes depressed, and rues the immorality of the scientific work she was once involved in. Jimmy, cuckoo in the scientific nest, is a throwback. He likes words. He has the sense his parents carry an internal report card on which his evaluation is always "Jimmy would do better ... if only he could try harder". As ever, Atwood's telling depictions of family life bristle with irony and pathos.

The Handmaid's Tale proceeded through a series of slow-motion tableaux. Oryx and Crake is all vigorous accretion of detail, like a trawl through the Web. Where the first was essentially a woman's world, preoccupied with conception and childbirth, this dystopia is a boy's world, full of nerds and hackers. It's a postmodern universe of (at least virtual) plenty, where you can choose your porn and everlasting face, as long as you belong to the elite.

Atwood seems to be implying that, as the maths, computers and biotech grow ever more complex, spawn ever more dangerous by-products, human relations become brutalised, reduced, two-dimensional. As if Asperger's were the name of the future game and reading emotions, like reading books, a trait which has been eroded in the survival of these particular fittest.

Yet this is also a buddy book. At school Jimmy, the misfit clown, meets his friend, Glenn, a super-intelligent nerd. Together they surf and hack. It is while surfing porn sites that they come across the child who grows into Oryx.

They also play two formative games. "Blood and Roses" lines up atrocities and genocides against human achievements. "Extinctathon" names the dead animals and charts the demise of species. Crake is one such, and the codename Glenn takes as he moves to Grandmaster status. Atwood underlines the fatal progress between games and the "real" world. It is Crake who heads the ultimate Paradice project. He calls Jimmy, now a not very successful copywriter, to his side to help do his PR. And it is from Paradice that the apocalypse is launched.

In Jimmy, Atwood has created a great character: a tragi-comic artist of the future, part buffoon, part Orpheus. An adman who's a sad man; a jealous lover who's in perpetual mourning; a fantasist who can only remember the past.

Like Winston Smith and Offred the Handmaid, Jimmy believes in the power of love. For him, it's too late. But he's not alone on his beach. In the burning sun which does them no harm, there are the beautiful, innocent green-eyed Crakers, the ultimate in genetic engineering. It is to their all-too-human Snowman that they come for stories of their "creators", Oryx and Crake. When he melts away, the only trace he may leave is in their memory, and their dawning ability to do the same.

Oryx and Crake is Atwood at her best – dark, dry, scabrously witty, yet moving and studded with flashes of pure poetry. Her gloriously inventive brave new world is all the more chilling because of the mirror it holds up to our own. Citizens, be warned.

Lisa Appignanesi's new novel, 'The Memory Man', will be published next year