The blind literally lead the blind -- to hell and back -- in the pretentious, preposterous allegory "Blindness."

An unnamed disease afflicts the unnamed citizens of an unnamed city, all of which is too precious. One by one, the victims are left sightless but they see white instead of black, a sensation one character compares to "swimming in milk." Once they're rounded up by soldiers and quarantined in a grubby, abandoned mental asylum (because apparently The Ritz-Carlton wasn't available), their worst primal instincts emerge: urination and defecation in the hallways, theft, assaults and, ultimately, rape.

The physical and moral deterioration calls to mind the situation in the Superdome after Hurricane Katrina but director Fernando Meirelles, in adapting a novel by Nobel Prize-winner Jose Saramago, is clearly trying to suggest that society similarly could collapse anywhere, anytime. Rather than being thought-provoking, though, the whole dreary exercise feels like an overlong beat-down -- as if we're being scolded just for showing up.

Somehow, "City of God," Meirelles' brutally violent 2002 drama about life in the Rio de Janeiro slums, was more subtle. Here, the director relies too heavily on obvious symbolism, such as glass reflections and various shades of white in the form of blazing sunlight or bright floor tiles. He even floods the screen with white at times, as if to make us feel what the characters are experiencing in Toronto native Don McKellar's script. If we share any emotion with these people, it's a yearning to get up and go home.

Even Julianne Moore can't liven up this slog, despite a typically strong performance as the one person who can still see -- a phenomenon which is never explained, probably because it's an arbitrary plot device. She pretends she's blind, though, to stay with her husband (Mark Ruffalo), who is an eye doctor. This means she can help navigate the chaos but only to a certain extent. She's also forced to witness it without revealing her secret and, therefore, risking her life.

Big Brother is watching as heavily armed soldiers who will shoot anyone who dares to step out of line but there's also a video playing on endless loop on monitors throughout the building, with a man spelling out the useless rules. This, too, feels heavy-handed.

Other victims include a little boy (Mitchell Nye), a hooker with a heart of gold (Alice Braga) and an elderly man (Danny Glover), all of whom were the doctor's patients. There's also a Japanese couple (Yusuke Iseya and Yoshino Kimura), the husband of which started all this when he went blind behind the wheel of his car in traffic. Then there's the bartender at the hotel where the prostitute worked (Gael Garcia Bernal), who appoints himself the King of Ward Three.

Basically, this means he takes over, adding a level of depravity to these already grim circumstances by forcing the others to fork over their valuables in exchange for the food he has hoarded. When there's nothing left of worth, he and his followers have their way with the women. If we'd known a single thing about him before his rise to power, he might have seemed more fearsome. Because he's barely fleshed out, his demands come out of nowhere and the group rape scene he orchestrates merely feels gratuitous.

Some of the visual imagery is striking in the post-apocalyptic wasteland outside the asylum. But then the laughably upbeat way in which "Blindness" ends only reinforces what a waste of time it was.

One and a half stars out of four.