By Adam B. Vary
Updated November 06, 2012 at 11:09 PM EST
Credit: Andreas Rentz/Getty Images

Taking on his first significant role in a major feature film since 2007, actor-turned-musician Jared Leto has signed onto Dallas Buyers Club, EW has confirmed.

The drama follows the real-life exploits of Ron Woodruff (Matthew McConaughey), a drug addict who contracted AIDS in the 1980s and ended up smuggling needed medication into the country for himself and his fellow patients — including a cross-dresser named Rayon, played by Leto. Jennifer Garner joined the cast last week as Woodruff’s physician. Gael Garcia Bernal was up for the role, but a deal never closed.

Ironically, Leto’s last role, as John Lennon killer Mark David Chapman in Chapter 27, required him to gain 67 pounds, whereas McConaughey has dropped 30 pounds to play Woodruff.

Jean-Marc Vallée (The Young Victoria) is directing the film, from a screenplay by Melisa Wallack (Meet Bill) and Craig Borten.

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