Mark Ruffalo says he lost 30 pounds to play one of two twins in HBO's I Know This Much Is True

Variety

HBO released the first images of Ruffalo's limited series, showing the actor playing two different-looking identical twins, one of whom appears heavier because he has a mental illness and has to take stabilizers and antipsychotics. Ruffalo shot the scenes where he played the other twin, Dominic, before putting on the pounds over a five-week period of force feeding. “When you’re force feeding yourself some of the romance of food leaves,” Ruffalo said at the TV press tour. “Those five weeks were kind of lonely, I’d been a way from my family and (Thomas) hears voices, and I was  imaging that life and there was a couple weeks where I was just staying by myself, going down into the heart of this mental illness and studying it.”