Dark parable: 'Children of Men'.

With a resume featuring A Little Princess and Harry Potter and the Prisoner of Azkaban, director Alfonso Cuaron knows his way around children's films. Now Cuaron has turned his expertise inside out, creating not a warm and whimsical world for and about children, but a cold and cruel one devoid of them. Both gut-churning thriller and dystopian sci-fi fantasy, Children of Men (based on the 1992 P. D. James novel) sets us down in the blighted London of 2027, a city beset by ruin and violence. In the opening scene, somber citizens crowd around TVs in bars and offices to watch news accounts of the death of a famous teenager known as Baby Diego, "the youngest person on the planet," killed in a melee after refusing a fan an autograph.

One pleasure of watching science fiction is the mental calisthenics involved in assimilating the daily realities of a future that has veered wildly off course (or, perhaps, stayed on course), mutating into strangeness. How can an eighteen-year-old be the youngest person on the planet? Why is London a war zone? What has happened to bring the world to such ruin? Cuaron keeps the backstory to an absolute minimum, letting us fill in a lot of blanks. A summary montage of news flashes implies massive destruction in the world's capitals. London has survived, but barely. Buildings loom tattered and graffiti-riddled. Factory chimneys belch sooty smoke. The streets are thronged with heavily armed soldiers and cowed citizens scurrying through their routines. Illegal refugees, reviled as "fugees," are hounded into squalid camps; throughout the city they stand in cages, waiting for transport. "The world has collapsed," intones a patriotic public-service announcement; "only Britain soldiers on."

While the setup is Orwellian, we learn next to nothing about Big Brother; the emphasis remains on the demoralized citizenry, caught in a never-ending hell of filth, violence, and barrenness. Literal barrenness, as it turns out. The calamity the world has brought on itself includes one particularly nightmarish aspect: global infertility. We don't know how, exactly--nor do the people in the film--but somewhere around 2008, women lost the capacity to conceive; Baby Diego was the last child born on earth.

Films of a dystopian future (The Terminator, The Handmaid's Tale, AI: Artificial Intelligence, Blade Runner) often invoke drastic ruptures in reproduction, with genetically or mechanically engineered pseudo-humans symbolizing a humanity so corrupted that it can literally no longer sustain itself. In Children of Men, no substitute has been devised, and humankind is staring extinction in the face. "Infertility is God's Punishment!" scream the street-corner placards of a doomsday religious movement. If so, it is less a punishment than an abandonment, on a scale not seen since the flood. God has repented of his creation and pulled the plug on man.

The movie's plot centers on Theo Faron, an employee at the Ministry of Energy, whose chain-smoking and ever-present half-pint of whiskey keep him distracted and numbed. A frightening episode reunites him with his former lover, Julian (Julianne Moore), now leader of a violent liberation group militating for the rights of the "fugees." In her charge is Kee, a radiant young African attempting to get to the English coast, where a mysterious group known as the Human Project waits to rescue her. And Kee needs rescuing because, as we soon learn, she has somehow succeeded where all others have failed for two decades: she's pregnant. Julian enlists Theo's help in getting transit papers--his cousin is a governmental higher-up--and drags him into the plot to smuggle Kee and her future baby to safety.

Children of Men leaves much unexplained. Who are the Human Project? What do they plan to do with the baby? You're not sure the filmmakers have it all figured out. Some movies deliver a powerful jolt despite having all sorts of holes, however, and this is one. The power resides in the look and the feel of the future that cinematographer Emmanuel Lubezki shows us, a bleak amalgam of The Terminator, Escape from New York, and Mad Max. Every turn discloses ruin, poison, violence, and degradation. Train windows are caged to protect passengers from howling mobs who hurl debris. In the countryside, a pyre of burning cattle smolders away as Theo and his friend Jasper drive by without so much as a glance. Why are cattle being burned? Plague?

It is a depressing world, and depressed as well, caught in deep collective despair as the slow countdown to oblivion proceeds. Theo himself, we learn, is mourning the loss of a son--a boy who died in the great flu pandemic of 2008. The film implicitly makes the connection, or perhaps extrapolation, from the grief of mourning a child to the still deeper grief of mourning all children. The prospect of humanity without a future devastates the individual psyche, and the compensatory aids society has devised are grotesque. Theo wakes to a TV commercial in which a man drinks some product and walks into the sunshine. "Quietus," soothes the ad's voice-over: "You Decide When." It takes a moment for us to realize that Quietus is a suicide drug.

This kind of film doesn't particularly depend on its actors, but the performances in Children of Men are more than serviceable. I've long admired Clive Owen, whose faintly damaged good looks are versatile enough to project glowering anger, glam suavity, or cool detachment; here he conveys a dazed and ravaged cynicism, the very visage of catastrophe. Michael Caine does a spirited turn as a former political cartoonist living in a house hidden away in the woods, a pot-smoking hippie whose cheerful black humor constitutes courage in a world where the soul has been beaten into submission.

Cuaron, meanwhile, takes us on a scary ride through the anarchic countryside, including one horrific chase scene involving a band of murderous thugs. Fleeing, Theo, Kee, and her friend, a midwife named Miriam (note the allusion to Miriam in Exodus, who hid the baby Moses), find temporary refuge in the ruins of a grade school. While Kee rests outside on a rusty swing set, Miriam recounts to Theo the onset of mass infertility--how one day she looked at her midwife calendar and saw, strangely, that she had no births scheduled. "As the sounds of the playground faded, despair set in," she recalls. "What happens to the world without the sound of children's voices?"

Children of Men takes lines that would seem melodramatic and sentimental and creates a world appalling enough to give them a primal resonance. Its makers released it just before Christmas, in time for Oscar season. But one suspects another motive behind a late-December film that enacts a nativity scene in a squalid refugee-camp building, or, in its most stunning moment, depicts a hideously violent firefight brought to a stop by a baby's cry. Despite its extreme violence, Children of Men shows a light touch with its deeper meanings, its ambiguous ending offering a glimmer of escape from the profoundest pessimism, by way of a quiet Christian parable. The film harrows you--then turns around and dangles a thread of hope. What if a fallen world truly could be redeemed by one miraculous birth?