'Blindness is a gift of the ugly," Julianne Moore observes in "Blindness," as a self-proclaimed "leader with vision," literally and figuratively. As the only character who can see, Moore makes for an unlikely and unwilling heroine.

Married to an ophthalmologist (a marvelous Mark Ruffalo) who just happens to treat the first victim of a worldwide epidemic of "white blindness," Moore's character stands by her man. She accompanies him when he, too, loses his sight and joins the humbled hordes of everyday folk thrown together by this sudden affliction.

Nameless yet central to the action, the stoic couple provides the voices of reason and calm in an otherwise horrifying sea of panic and resignation. Both performances are consistently compelling; their dedication and selflessness make the rest of the story and its petty rivalries pale by comparison.

After showcasing the more jarring visual aspects of the daily urban grind -- ones we might not miss if blind -- director Meirelles immediately tears the veneer off civilized society and delves into the mysterious ailment. It's a democratic disease that makes no distinction between rich or poor, black or white, young or old.

And with steady intense focus on the human toll -- patience, kindness -- this depressingly unnerving morality play does not shy away from the demons that quickly surface in the absence of laws, communal mores or even basic comforts such as food, clothing and water.

"Either the blindness spread the panic or the panic spread the blindness" is the theory. Either way, both become epidemic. When order can no longer be maintained and the law, armed and wholly unsympathetic, cannot contain the uprising, anarchy awaits.

Quarantined in dark, disgusting quarters, the victims try to adjust and form a society of their own. Tempers flare, shortages abound and food rationing is the new reality.

Although stripped of cell phones, random patients manage to elude the guards and smuggle in a knife and a gun (with ammo! -- can you say "plot device"?). Locked up with insufficient everything, the inmates take over the asylum (literally -- they're in an abandoned sanitarium). Power abhors a vacuum; here, it is quickly filled.

When food becomes currency, the armed first demand jewelry and valuables, then the services of female "volunteers." As the cocky, self-appointed "leader" of Ward 3, a disturbingly callous Gael Garcia Bernal radiates rage and greed.

Grim, gray and ultimately humorless (even "Titanic" and "Coma" included multifaceted characters with some warmth or wry wit), "Blindness" presents a sad commentary on the flimsy fabric of unity in time of crisis, harshly proving that people do what they feel like doing according to whatever morality they have left.

The atmosphere recalls the opening pages of Camus' "The Plague" -- disease, deteriorating sanitary conditions, rodents, etc. The streets are overrun with debris, and the survivors are forced to compete for food and dignity, while fighting each other to stay alive.

There's only an occasional hint of our better instincts. The weak dialogue and tense action challenge us: We can see, but do we want to? Do we dare look away? And if the government has given up on the sick, why should anyone else care?

Somewhere among the suffering, abuse and domination, "Blindness" aims to convey a noble, humanitarian message. Sadly, we may not be able to see it.

Get $150+ in coupons in every Sunday N&O. Click here for convenient home delivery.