Watch an Emaciated Matthew McConaughey in 'Dallas Buyers Club' Trailer

Matthew McConaughey is usually associated with a buff exterior and occasional romantic comedies.

This is all about to change in a big way, as the 43-year-old is set to star in "Dallas Buyers Club" as Ron Woodroof, a Texas playboy living with AIDS in the late 1980s.

The newly released trailer opens with Woodroof"s diagnosis, and includes a hospital scene in which McConaughey's much-talked-about weight loss for the role is much in evidence.

Read: Matthew McConaughey's Extreme Weight Loss

The clip continues as McConaughey's character travels to Mexico to tap in to some illegal HIV meds that seem to help him and others get back on their feet.

Jared Leto also makes an appearance as a cross-dressing salesman for Woodroof, peddling these illegal supplements to other AIDS patients.

Related: Matthew McConaughey on What He's Learned as a Dad

"I got one life, I want it to mean something," Woodroof says.

"Dallas Buyers Club" is slated for an early November release.

(Photo Credit: Anne Marie Fox/Focus Features)