His dark materials

It's one thing to adapt literature to the screen and to do so by the book. It's another for a director to dare to make the works his own.

Steve Zaillian took the first direction with his remake of "All the King's Men," and results were cautionary. When the Mexican director Alfonso Cuarón has adapted books to the screen -- Frances Hodgson Burnett's "A Little Princess" in 1995, Dickens's "Great Expectations" in 1998," and "Harry Potter and the Prisoner of Azkaban " in 2004 -- the results have been transforming.

His new film, "Children of Men," based on the dystopian thriller by British mystery writer P.D. James, cements Cuarón's reputation as a filmmaker who can take another person's vision and make it his own. While English may be Cuarón's second language, cultural differences don't deter him from placing his mark squarely on works he's chosen to adapt.

"For me, there is a common language," says the 45-year-old Mexico City native. "You just do the films that you feel are right in the moment. They are the films you need to do."

"Children of Men," which opens tomorrow , drops us into London, year 2027, a world where no woman has given birth in 19 years. Society has plunged into despair, terrorism, and martial law. In the film, Clive Owen plays Theo, an activist-turned-bureaucrat who's forced to confront his radical past that includes Julian (Julianne Moore), a former lover and refugee-rights leader, and Jasper (Michael Caine), an aging militant. A young immigrant woman named Kee (Claire-Hope Ashitey) must travel illegally across England to reach a fabled group called the Human Project and, hopefully, to help steer civilization back on the right path. Julian persuades Theo to help.

"The premise [of infertility] is a metaphor for the failing sense of hope for humanity," says Cuarón.

It's also a metaphor for our lack of historical perspective, he adds. Our present approach to life focuses on the enjoyment of today. That dark material drew Cuarón in, and he worked hard to draw parallels to present-day conflicts and how they might be echoed in some future form.

"If I told you 30 years ago, I want to do a movie where there is massive immigration from the undeveloped countries to the developed countries," Cuarón says, almost gleefully, "and the US has backed out from the Geneva Accords, and is spying on its citizens, accepting torture, and building a wall between Mexico and the US, you'd say, 'Come on!' "

With graying black locks and a beard, the slim Cuarón is dressed in somber clothes. His accented speech is laden with phrases from his days as a cinema and philosophy student at the National Autonomous University of Mexico: "hedonistic economy," "liberal humanism," "denial of the consequences."

To explore these issues, the filmmaker followed the thread of environmental degradation and immigration but took a completely different approach than James's book. Producer Marc Abraham says when he got Cuarón on board, he knew he would be getting a distinctive take on the material.

"Alfonso was less interested in the script than he was in the basic premise," Abraham says via phone from Los Angeles. "If you look at anything he has done, you can see that he is a very dynamic filmmaker with a very personal vision. You're confident that he's going to tell the story in his way."

To do that, Cuarón discarded the original scripts and wrote a new one (with four collaborators) from scratch. Then he built his world. This approach was a huge adjustment from the Harry Potter book, which in Cuarón's words has "a very well-oiled machinery" and "a specific universe with very specific rules."

In "Children of Men," Cuarón's challenges were to create a plausible and disciplined future England, where the sets, locations, and social environment would be as important as the characters. "The toughest thing was to create the environment, to define the universe that we were portraying."

First and foremost, he was determined his film wouldn't devolve into run-of-the-mill future-shock. "We didn't want to do a science-fiction film," Cuarón says. "We were very concerned about alienating the sense of the present." By that Cuarón means, no high-tech gadgetry for its own sake. Everything -- every bus, building, and billboard -- had to have a reference to the present day.

Cuarón recalls that his art directors produced concept drawings that were impressive but completely wrong: " 'Cities of the future' and futuristic cars." "And I said 'Thank you very much.' But I brought my own file that was photographs of Iraq, of Northern Ireland, the Balkans, Somalia, northern Sri Lanka, [and I said] 'This is more like the movie we're going to do.' " The future would be dirty, sweaty, worn - out, a wreck. No shiny cars. No shiny people.

"We had to begin with things that would have existed [in the present day]," he says. Some items, like video games, were given a nudge into the future. Others would be stuck in the past. "We assumed that around 2012, technology started to stand still . . . like in Havana, that all the cars are old."

No sleek totalitarian government, either. The political system had to be eerily familiar, but twisted; advanced, but deteriorated. Not a dictatorship, as in James's book, but a malevolent democracy, complete with security forces grown imperious after years of insurgent attacks.

This concept was partly born of Cuarón's experience under Mexico's PRI party, which ruled Mexico as a de facto one-party state for seven decades, until 2000. At the time of Cuarón's visit to Boston, Mexico was still sorting out its latest election results. "We have two presidents now. Everything in Mexico is cheap labor," the director jokes. "We can afford two."

The filmmaker tempers his ironic outlook with a fastidious visual language -- one whose roots can be seen in the tragicomic road movie "Y Tu Mamá También." In that film, the camera effortlessly hovered around the protagonists' car as it traveled through the Mexican countryside. In "Children of Men," Cuarón and his cinematographer, Emmanuel Lubezki, staged elaborate car chases, choreographed violence, and set up extremely long takes, some as long as eight or nine minutes.

Each of these "one-shot deals" became, in Cuarón's parlance, "a moment of truthfulness . . . which the camera is there just to register." The long takes advance not only the story, but the director's storytelling aesthetic. Namely, that social environment is as important as character.

"So, visually you don't weigh one more than the other. There are no close-ups. You allow your characters to blend with the environment," he says. "It's a comment of the social environment and starts to become a comment of our contemporary society."

The film's visual tour de force comes toward the end: a lengthy battle in a refugee camp that Cuarón shot on a British air force base. The characters of Theo and Kee run through this melee, and a camera follows them through explosions, tank fire, and swarms of extras.

"I think a lot of people don't understand the mastery [required for this kind of shooting]," Abraham adds. "Like with Matisse or Picasso, you know when they sat down to draw a woman reclined with a pencil and never picked it up from the paper? It's a little like what [Cuarón] chose to do."

For the climax, Cuarón spent 12 days dressing the set, rigging it with special effects and rehearsing his actors -- and only two days rolling film. He got the perfect take in the final hours of the last day of shooting. When he noticed fake blood had spattered on the lens, at first he was horrified. Then, he was thankful.

"With all the tricks, what you want is a moment that really exists," he says. That includes elements you can't control. "Even accidents like the blood on the lens."

Everything is planned "milli-metrically," but it's mistakes Alfonso Cuarón craves. They counter the artificiality of moviemaking. In the case of "Children of Men," the dirt, errors , and chaos also make the future -- and his vision -- more real.

Ethan Gilsdorf can be reached at ethan@ethangilsdorf.com.