Blindness is a metaphor run amok, visually thrilling and maddeningly vague. Director Fernando Meirelles (City of God, The Constant Gardener) creates an unforgettable experience; what it's really about is up for grabs.

Based on Jose Saramago's novel, Blindness plunges anonymous citizens of an unnamed city into contagious, spontaneous sightlessness, for reasons never explained. One victim is an opthomologist (Mark Ruffalo) whose wife (Julianne Moore) is somehow unaffected. She bluffs her way into quarantine with him, in an abandoned mental institution without any direct supervision, only armed guards with nervous trigger fingers.

Others affected should be happy they can't see what she sees: a disintegration of humanity and hygiene leading to murderous anarchy. One sequence in Meirelles' movie depicts women submitting themselves sexually to jackals controlling food supplies, as disturbing as anything seen lately on screen. Sex is apparently a symptom of the disease, with victims copulating in our plain sight, even a prostitute with the doctor (who should know better since his wife could be watching).

Carnal instinct is the main thing separating Blindness from other apocalyptic plots. Yet Meirelles expresses every fear and atrocity with such vivid artistry -- this is "white blindness," so the screen is often awash in milky light -- that he must have something deeper in mind.

On the morning after the stock market fell 777 points, Blindness felt like watching Wall Street brokers eating each other. Others may view the blindness as political symbolism, or perhaps AIDS or Guantanamo Bay. Yet for all his sensory brilliance, Meirelles doesn't convince us to think about it much after the show.

(Photos from Miramax Films)