I think the filmmakers picture themselves on TV, dressed in classy Prada suits and discussing Relevant Social Issues with Stone Phillips: "Can individuals really make a difference in these troubled times? The movie that's sparked a surprising movement for a new personal morality, next."

Even that may be giving "Pay It Forward" too much credit. It doesn't have anything to say about ethics or idealism, even by MSNBC standards. Without its stars, it's an insultingly shallow weeper-of-the-week that would make a Lifetime executive blush. Furthermore, its falseness runs deeper than a lame stab at being meaningful. This brightly colored fable from "Deep Impact" director Mimi Leder (the screenplay is by Leslie Dixon, from a novel by Catherine Ryan Hyde) professes a sentimental adoration for children, but there's a hysterical edge to that adoration that makes it feel like something much darker. Essentially, "Pay It Forward" is a paranoid Christian fantasy in which the world is a place of evil and ugliness that demands to be purified through the sacrifice of innocents. I wasn't much of a Catholic even as a kid, but I recognize a hagiography when I see one.

Maybe cocktail waitress Arlene McKinney (Hunt) and schoolteacher Eugene Simonet (Spacey) would never have found each other without the intervention of Arlene's son, Trevor (Osment), a seventh-grader in Eugene's social studies class. But how long they can stand to be in the same house with this impish know-it-all is another question. The most satisfying moment in "Pay It Forward" arrives when Arlene hauls off and pops Trevor one after he tells her, "I hate the way you look! I hate the way you smell! I hate that you're my mother!" The movie's portrayal of the relationship between children and adults is so confused it's hard to say who's abusing whom. And at least it shuts up the little creep for a while.

Hunt has imported her "struggling single mom" shtick pretty much intact from "As Good as It Gets" (an awfully similar movie, truth be told) and it still works, though I'm not exactly sure why. In that movie she played the only impoverished WASP in the entire borough of Brooklyn, N.Y.; here she's the only white woman in Las Vegas under age 80 who rides the bus.

With her frizzed-out hair, skimpy outfits and trailer park makeup, semirecovering alcoholic Arlene looks like Erin Brockovich after a three-day bender. She probably lives next door to Nomi, the heroine of "Showgirls." But amid all the phony trappings of movieland working-class life, there's so much that's genuine about Hunt as a performer -- her screwball klutziness, her desire to be liked, her slightly frayed sex appeal -- that I couldn't resist Arlene for more than a few seconds. Watching competing emotions work their way across her face (approximately: "I like this guy. What's wrong with him? What's wrong with me?") while Eugene summons up the courage to ask her out is worth the price of admission all by itself.

As ever, Spacey plays an off-center guy with a secret. In this case it's not an interesting secret or an especially well-concealed one, and for all Spacey's uncanny physical work Eugene remains a cipher. In the first scene we see him ironing his own shirts, and that's about as much character insight as we ever get. Eugene is a lifelong loner with an untended haircut who wears shabby suits with running shoes and likes to show off his collegiate vocabulary. (Words like "atrophy," "exigent" and "euphemism" stick out in a Vegas middle school.)

In short, he's the inscrutable, noble and damaged hero of a romance novel, rather than an actual human male. As far as we or Arlene can tell, he's a virgin. We know he's scarred because, well, he's scarred. Duh! His face is marked with mysterious burns, like Jane Eyre's boss after the fire. When Trevor asks what happened to him, Leder's camera abruptly slips sideways, just in case we hadn't noticed that this is an important question.

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