In role after role, he has remained anonymous, so much so that eyebrows were raised when he was nominated for best supporting actor last year for "Winter's Bone."

Now he is being propelled farther into the limelight in a starring role that awards voters traditionally love -- a writer crippled by polio -- opposite Helen Hunt in "The Sessions," a feel-good inspiring indie movie aiming for wider appeal when it is released in the United States on Friday.

"There is trepidation alongside the gratitude," Hawkes said in an interview about his rising status, adding that while he "doesn't want to seem ungrateful," he knows with acclaim comes "things that are actually detrimental to being an effective actor."

"The Sessions" is based on the story of Mark O'Brien, an American poet and journalist who died in 1999, aged 49, who spends his days being wheeled around on a gurney and nights trapped in an iron lung. The film shows O'Brien hiring a sex therapist, played by Hunt, to lose his virginity.

It premiered to a standing ovation at the Sundance Film Festival. Then called "The Surrogate," it was a breakout hit there. It has received rave reviews, including for the performances of Hunt, and Hawkes, who for the entire film is limited to movement mostly above the neck.

"Just the notion that you would be playing the lead role in a film and you would only be able to move your head 90 degrees and every other part of you would have to remain twisted and still, gives you pause as an actor," Hawkes said.

He was offered the role by writer and director Ben Lewin on the back of his "Winter's Bone" success, in which he played a menacing meth addict and before that an evil cult leader in the film "Martha Marcy May Marlene." He is best known for his recurring role of Sol Star in the TV series "Deadwood."

"Ben rented 'Winter's Bone' and reported back, 'That creepy old guy?'" Hawkes said.

By then Lewin, himself a polio survivor, checked previous roles in a career spanning more than 25 years. They met and clicked.

"I don't know if he had a lot of choices at the time," said Hawkes, who at 53 looks young enough to play O'Brien aged in his late thirties.

HUMANIZING O'BRIEN

After Hawkes signed onto the film, Hunt followed, as did William H. Macy, who as a priest counsels O'Brien, a fervent Catholic, and offers advice in often humorous scenes.

Lewin shot the film in chronological order in a 22-day shoot to make the sex scenes between Hunt and Hawkes seem authentic.

"Sex scenes are often awkward to shoot and made to look flawless and like the perfect fantasy -- and we weren't interested in that," said Hawkes. "It was a wise choice that Helen and I didn't pal up and have dinner and get to know each other, so that awkwardness, unfamiliarity, nervousness, is all real."

He spent two months before filming practicing O'Brien's high-pitched voice and mannerisms seen in the Oscar-winning 1996 documentary short film, "Breathing Lessons: The Life and Work of Mark O'Brien."

Training himself to lie still, he learned to use a mouth stick and did not have the aid of prosthetics or a body double to replicate O'Brien's extreme curvature of the spine. Instead, he used a "soccer ball-sized piece of foam" placed behind his back to pronounce his rib cage.

He wanted to ensure during filming that "I would forget I was horizontal and just thought of myself as a human being," he said.

He often consulted the real life Cheryl Cohen Greene, who Hunt plays, and Susan Fernbach, O'Brien's partner in later years.

The film offers the message of living life to the full and facing one's fears. These are lessons Hawkes, who dreamed of being creative after appearing in a play aged 16, seems attuned to.

"Since that moment it has been in my blood, to, if nothing else avoid the straight world," he said.

(Editing by Patricia Reaney; Editing by Kenneth Barry)

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