Matthew Mcconaughey plays a cowboy in his latest film, Dallas Buyers Club. And he could be riding a dark horse into the 2014 Oscars with his role as Ron Woodruff. Jared Leto, too, is being mooted as a strong underdog.

Matthew McConaugheyMatthew McConaughey as Ron Woodroof in Dallas Buyers Club

Woodruff was a tumultuous character, homophobic, drug-addled and violent. This was until he was diagnosed with HIV and given 30 days to live. He then set about creating one of the most elaborate drug rings America has known.

But he wasn’t dealing in narcotics. Heroin, cocaine and amphetamine weren’t passing through the Dallas Buyers Club, but medicines to fight HIV/AIDS that weren’t ‘approved’ by the American board of medicine.

See what the critics are saying about The Dallas Buyer's Club

McConaughey is being lauded for his turn as the mercurial Woodruff. His diminutive stature doesn’t stop his on-screen presence being larger than it’s ever been. Ever charming, there’s an aura of tension around his shaky delivery and shady cadence.

That diminutive stature didn’t come about by accident or visual trickery; he had to shed the weight. “I was going around and people were going, ‘Hey, are you feeling all right?’” he said, describing the weight loss.

Matthew McConaughy and Jared LetoMatthew McConaughy and Jared Leto

“But then I hit 135 lbs. I ran in to somebody and they didn't just ask if I was all right, they said, ‘My God, we need to get you some help.’ And I thought, ‘There we go. That's the perfect spot.’” (Vanity Fair)

Leto plays Rayon - a transgender woman living with HIV and struggling with a drug habit. She/he forms an unlikely friendship with Woodruff, and end up sharing the trials and tibulations that come with the Dallas Buyers Club.

“These little films, they can break your heart. I tend to make smaller films, independent films, and it's a risky business,” said Leto on making independent films, like Dallas Buyers.

“You have to be really careful about what you do. But when I read the script I thought that this was a worthy experiment and I was really, really excited to work with this incredibly gifted group of people.” (NPR)

With films like Gravity and 12 Years a Slave leading the race for Best Picture, the individual gongs are far less easy to call, and either one – or both – of McConaughey and Leto could be in line for a surprise read-out.

Check out the trailer for Dallas Buyer's Club