Heath Ledger in <EM>Brokeback Mountain</EM> Heath Ledger in Brokeback Mountain

Based on a short story by Pulitzer prize-winning author Annie Proulx, director Ang Lee's Brokeback Mountain (hitting select theaters today) presents Heath Ledger and Jake Gyllenhaal as Ennis and Jack, hired ranch hands who, during their isolation on a sheepherding job, discover an intimacy and, ultimately, a love that, in a 1960s setting, dared not speak its name.

Partaking in what undoubtedly will be much-scrutinized fare was a significant leap for Ledger. But rather than be deterred by what "some people" might think, he only saw a can't-miss opportunity. "This is obviously the most complex and internal character that I have been offered," says the star of such past films as Monster's Ball, A Knight's Tale and 10 Things I Hate About You. "I knew it would demand a more matured performance out of me."

Plus, he notes, "It was the perfect script, the perfect director and a story that hadn't been told, which is extremely rare." On the flip side of thinking he'd be nuts to take it on, Ledger says, "I thought I'd be crazy to turn it down."

Throughout his press tour for Brokeback, Ledger has repeatedly faced questions about the love story's gay element, and how he and Gyllenhaal found their comfort levels with it. "Everyone always asks, 'What was the most difficult aspect of the movie for you?' or, 'Physically, what was the most difficult?' Making out with Jake Gyllenhaal!" Ledger answers with a laugh. "It's a really obvious answer to give. But at the end of the day, once we got the first take out of the way, it was like, 'OK, alright, whatever. Let's continue.' All the mystery had been taken away. It wasn't such a big deal."

In a recent Details interview, however, Gyllenhaal posited that Jack and Ennis are not necessarily gay, eliciting a mini-uproar (if not a chorus of rolling eyes). "It's a touchy subject," Ledger nods. "For me, this was the story of one person and his soul falling in love with another soul, and one that comes in the form of another man, and how incredibly strong and instinctual that love can be. I don't want to say it's not a gay story and not a gay relationship because it is, and there would be a lot of people who would be really upset if we took that away from the film. [All I'm saying is that] the point is bigger than that. It's love on a much bigger scale.

"Unfortunately," he adds, "society likes to label things. I hope this film exceeds that label; the short story sure did."

Whether read as that short story or seen in a theater, Brokeback Mountain is an affecting experience, a tortured love story — and not just for the star-crossed cowboys, but also the wives (Michelle Williams, Ledger's on- and off-screen love, and Anne Hathaway) held at a distance by their husbands' extramarital leanings — told against breathtaking vistas. "There are two sides to how it affected me," shares Ledger. "One was, while filming it, you're affected by what you're portraying. If all day, every day, you're tricking yourself to feel anger, you get home and are like, 'Argh! F---, why am I angry? I've got no reason to be angry.' So you have to wind yourself down again.

"And two, when you see the movie, it affects you. The first time I saw it, it was with Michelle, and we weren't really sure what we thought, we couldn't really separate ourselves from it. It wasn't until I saw it in Venice" — whose film festival named Brokeback best picture — "with an audience, and their attention and emotion bled into my own experience as an audience member. That's when I appreciated it a bit more. I definitely stood up and was proud."

As Brokeback's release schedule expands — it arrives in more cities on Dec. 16, then goes wide in January — surely will the number of critics touting him as a front-runner in this year's Oscar race. The actor's take on it all? "I don't know. Michelle and I certainly don't talk about it when we're at home. I find it a strange concept that movies and performances can be competed against, because we're all competing in completely different races and nobody is starting from the same point or ending at the same point."

No, his greatest reward to be gleaned from Brokeback is the lady he met during filming, has come to love, and with whom he has a 6-week-old daughter named Matilda. Falling in love with Williams, Ledger says, "is the best thing I got out of this. We are forever grateful."