Sometimes it's all about the buzz. Sometimes the buzz is orchestrated to make a buck or to make a point. Sometimes, as in the case of Ang Lee's "Brokeback Mountain," the buzz is a justifiable manifestation of the social relevancy of a particular work of art.

	Focus Features Heath Ledger, left, and Jake Gyllenhaal in "Brokeback Mountain." Click photo for larger image. 'Brokeback Mountain' Rating: R for sexuality, nudity, language and some violence. Starring: Heath Ledger, Jake Gyllenhaal. Director: Ang Lee

For better or worse, we live in an America where millions of Republicans and Democrats recently voted together to ban gay marriage in their states, or at least to legally define marriage as a union exclusively between a man and woman. Months before anybody had even seen "Brokeback Mountain," the mere awareness that a mainstream movie about two Marlboro Men in a sleeping bag was on the way made it A-1 water-cooler conversation among homophobes, gay rights activists and everyone in between.

In fact, "Brokeback Mountain" isn't the first commercial movie depicting homosexuality. It's not even the first film with big stars playing gay characters. Here's what else it's not: Village People queers in chaps, homos on the range, or high-mountain promiscuity. With the exception of some AIDS tragedies, mainstream Hollywood hasn't fully explored the long-term romantic commitment of two men. "Brokeback Mountain" does. It's a challenging, well-scripted, beautifully filmed rendering of that minority aspect of the human condition.

Based on a short story by E. Annie Proulx, it's a tragic drama about a long-term forbidden love affair. Two stoic young guys hired to shepherd sheep for the summer spend months alone in the mountains. One is aware of his bisexuality, the other has never considered it. The affair begins almost by accident and grows into a powerful love that spans decades, influencing their lives and altering the lives of those around them.

Director Lee could have turned this into pornography or advocacy propaganda. Instead, he thoughtfully explored varied aspects of a timely, controversial issue and turned it into art.

As much as Heath Ledger overplays his testosterone-dripping "Casanova," he's almost deadpan as Ennis Del Mar, a quiet, mumbling, underemployed ranch hand who's shocked by his reaction to a gay encounter and overwhelmed by the power of the continuing relationship. As the years unfold, he's tortured by his secret love for a man and the damaging impact his affair has on his wife and family.

Rodeo rider Jack Twist masks uncertainties about his sexual preference behind daring acts of bravado, but accidentally finds a soulmate in the awkward ranch hand Ennis. Jake Gyllenhaal offers a powerful performance as a man struggling to free himself from an all-consuming yet tragically unsatisfying love.

Ennis and Jack spend a summer alone on Brokeback Mountain and a lifetime alone in a hopeless, long-distance love affair. They're drawn to each other, but can arrange only one week a year to slip back to the mountain for "fishing" adventures, trysts which are ultimately spoiled by the inevitable discussion of their past and uncertain future.

No characters are sympathetic to their relationship. Randy Quaid plays a suspicious and gruff ranch owner. As Ennis' troubled wife, Michelle Williams keenly articulates the impact of an affair on the family.

Having seen "Brokeback Mountain," I can promise you two things: It's not a social contagion planted on the screen to infect America's youth, and the water-cooler comics who've been making all those gay-cowboy jokes without seeing the film are going to look really stupid on Monday morning.

"Brokeback Mountain" is at Loews and Manor theaters.