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Mark Ruffalo, 52, may play both identical twin brothers in the HBO series I Know This Much Is True, but the characters can’t exactly be described as doppelgängers. This is because Mark underwent extreme weight changes to film as each brother. The most radical transformation, however, was apparent in his role as Dominick Birdsey.
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In the series adapted from Wally Lamb’s novel of the same name, Dominick takes care of his twin, Thomas, who suffers schizophrenia. To accurately portray Dominick’s nature as the “neurotypical brother,” he went on a 1,000 calorie-a-day diet to drop 20 pounds, writer and director Derek Cianfrance told The Wrap in an interview published on June 13. “I guess you could say he was always a little bit hangry. He was eating an egg white for breakfast and just starving. And he couldn’t eat for another 3 hours, and all he could eat then was a granola bar that had 120 calories or something, because he was on this strict diet,” he explained.
The drastic diet “created this guy Dominick who was just wiry and aggressive,” the writer and director added. Food wasn’t the only major change in Mark’s life as he prepared for this role. Derek estimated that Mark did “probably 500 pushups a day,” in an effort to recreate a cigarette smoker who always seems out of breath.
“I was like, ‘Well, you’re just becoming Dominick — this guy who’s just struggling for every breath. This guy with a barrel chest,’” the director/writer said on why he pushed Mark to do so many pushups in between takes. For 16 weeks, Mark adapted to this new lifestyle while filming his scenes as Dominick, and put on 30 pounds to play the other twin brother.
“The twinning, I knew was going to be a challenge and playing someone that mentally ill and that sick was going to be a challenge,” Mark admitted in an HBO video interview, uploaded on April 29. The Avengers star appears to be at a healthy weight, now, as seen in a photo taken backstage at The Graham Norton Show (above) that he shared on May 21.