What a mystery: How can a movie so spare and bleak be so emotionally rich? Watching the blasted, gray skies and ash-covered landscape of "The Road," you wonder how this film could be anything but a fatal downer. And yet the adaptation of Cormac McCarthy's Pulitzer-winning novel about a father and son navigating a post-apocalyptic wasteland is as joyous a cinematic experience I've had this year.