In keeping with the source novel by P.D. James, director Alfonso Cuaron's film version of Children of Men begins with a newscast that informs Earth's dwindling residents that the youngest living human has been stabbed to death.

This is heartbreaking news to those populating the gritty setting of the film - women have become infertile and gang warfare is rampant - and gives Cuaron the perfect backdrop on which to create his eventual sense of hope.

In keeping with the source novel by P.D. James, director Alfonso Cuaron's film version of Children of Men begins with a newscast that informs Earth's dwindling residents that the youngest living human has been stabbed to death.

This is heartbreaking news to those populating the gritty setting of the film - women have become infertile and gang warfare is rampant - and gives Cuaron the perfect backdrop on which to create his eventual sense of hope.

This progression begins with a pregnant refugee woman (Claire-Hope Ashitey) and the blank-eyed, cynical man enlisted to protect her (Clive Owen). Weaving through British cities that have become little more than concrete shooting ranges, the pair tries to smuggle the world's only fetus to a sanctuary kept by the altruistic but ill-defined "Human Project."

Theirs is no easy passage, as Cuaron, director of Y Tu Mama Tambien and Harry Potter: The Prisoner of Azkaban, is determined to play up the filth and danger that dominate a world without children.

He gets a bit preachy - all government officials appear heartless, corrupt cable news advertises suicide products - but those are small details that spoil neither the gripping drama nor the stand-out performances of the two unlikely protagonists.

Owen is subtle and tough, and he gives depth to a character that nearly any other actor working in Hollywood would reduce to the hard-drinking, devil-may-care leads that unfortunately overtake many action films. (Midway through the film, he changes his mind about his decisions without having to explain out loud why he's doing so - a rarity these days.)

And partnered with Owen, the wary yet kind Ashitey is perfect as a mother who's as scared of dying as she is of losing her baby.

Audiences will begin the film asking questions (Why the infertility? Where's the genetic research? Didn't this happen kind of fast?), but by the end most will be wooed by what boils down to a complicated but life-affirming message.

Grade: A Web: www.childrenofmen.net