'Dallas Buyers Club' Trailer: Matthew McConaughey and Jared Leto as Unlikely Duo Battling HIV

The "Magic Mike" star portrays a real cowboy who helped save lives by smuggling unapproved AIDS medications into the U.S.

Matthew McConaughey has generated no shortage of buzz for Dallas Buyers Club, a biopic from director Jean-Marc Vallee that required him to lose a dramatic amount of weight to play Ron Woodroof, a Texas cowboy who smuggled unapproved anti-viral drugs from Mexico after contracting HIV in 1986. Now comes the first trailer for the film, which was acquired by Focus Features and is set to debut at the Toronto International Film Festival.

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The physical transformation is indeed startling, from an actor associated with a buff torso and frequent shirtlessness whittled down to a skeletal frame and covered in cancerous lesions. He soon receives a devastating diagnosis from a doctor hidden behind a surgical mask: one month to live. That death sentence sets the plot into action, as Woodroof, a bull-riding brawler, is determined not to go down without a fight. 

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McConaughey has had a midcareer renaissance with a string of standout performances in indie films such as Bernie, Killer Joe, Mud and Magic Mike. Dallas Buyers Club could be the vehicle to nudge him toward major awards recognition this year. But don't count out co-star Jared Leto, who gamely embodies Rayon, a cross-dresser also battling the deadly disease. With the help of a compassionate doctor (Jennifer Garner), the unlikely pair teams up to launch an illegal HIV drug-running scheme that spreads across the country, saving many lives.

Dallas Buyers Club hits theaters on Nov. 1.