A couple of years back, the young Mexican superstar Gael Garcia Bernal urged me to look up his buddy, director Alfonso Cuaron. "You'll really like him, man!" Turns out catching up to auteur Cuaron would prove to be the hard part, when a man is so in demand that his work leaps across genres and borders. From his early-90s dark comedy about a straight, macho guy who contacts AIDS; to an award-winning American cable series; to adapting a beloved children's book; to updating Dickens; to casting two young studs of the New Mexican Cinema, friends since childhood, in a torrid love scene; to directing the Harry Potter episode most beloved by Potter's creator; to his latest project, adapting bestselling British author P.D. James' apocalyptic novel Children of Men for the screen, Cuaron is a man who doesn't stay in one place for long.

Cuaron's version of James' Children of Men is a very bleak look at a near future where the human population has become sterile, the youngest humans are now tabloid celebrities, and an Orwellian-style British government has virtually banned all immigration, with illegal aliens hunted down like typhoid carriers by squads of brutish police.

Into this toxic miasma, Children focuses on the efforts of a feckless bureaucrat (Clive Owen) to smuggle the world's lone pregnant women through a gauntlet that makes the current skirmish in Iraq seem downright agreeable. Cuaron's film borrows the outlines of James' Catholic allegorical novel, while focusing on the very hot immigration issue. Cuaron thinks that the current immigration dustups, whether in Europe or between his native Mexico and the US, are aggravated by distorted perceptions of alien workers in the media.

"Right away it sets the standard, 'We have a problem. People are getting into our house,' without exploring the reasons why this issue is going on."

Cuaron argues, "The idea of setting a wall between Mexico and the US is the kind of archaic solution that will completely backfire. A big percentage of the Mexicans coming into the States earn their money, then try to return to enjoy their money. With tougher immigration measures, they realize it will be tougher to go up and down, so why not bring the whole family? Once you bring the whole family, you might as well stay here."

Cuaron had a ball shooting the film with actors like Clive Owen. "I consider him a collaborator." He says Michael Caine based his pot-smoking New Age guy on the late John Lennon, "He knew John Lennon, they were friends," He thanks Queer as Folk veteran Charlie Hunnam for bringing a scary quality to his relatively small role as a British anti-immigrant soldier.

Cuaron says his depiction of the violent urban warfare in the film was intended "not to glorify violence, but to represent the unglamorous crudeness of real violence."

He describes with delight the bygone chapter shooting his pioneering teen comedy, Y Tu Mama Tambien, with ravishing newcomers Gael Garcia Bernal and his childhood buddy Diego Luna. The day of the now-famous kissing scene, he observed the two actors start to exhibit macho-like panic — hugging women on the set, excessive drinking, anything to deny the implications of two best buddies simulating the throes of sexual passion. A hilarious moment occurred after several takes, when Diego turned to Gael and whispered, "Hey, you're a good kisser!"

Directing the third Harry Potter movie, Cuaron came away with a strong impression of the red-haired but bashful Rupert Grint as the likely future star out of the Hogwarts trio. The director noted that it was interesting to observe Grint's shyness with girls compared to Garcia Bernal's legendary affinity for the ladies. "Gael, he was seven, and he was sleeping with all the girls in the kindergarten."