Mark Ruffalo Says It Was 'Really Challenging' to Gain 30 Lbs. for I Know This Much Is True

Mark Ruffalo didn’t hold back when it came to transforming into his latest character.
At the TV Critics Association Winter Press Tour on Wednesday, the 52-year-old actor revealed he gained 30 lbs. for his role in the upcoming HBO miniseries, I Know This Much Is True.
In the show, Ruffalo stars as two very different but identical twin brothers, Dominick and Thomas Birdsey. The actor filmed all his scenes as Dominick for the first 15 weeks, before taking five weeks off to transform