Why Adrien Brody was never the same after The Pianist - Looper

In order to step into Szpilman's shoes, Brody dove head first into the world of method acting. He knew that he could never fully understand what the real-life Szpilman had experienced, but he had to try his best to get inside his head. The first step? Actually learning how to play the piano so that he could perform the Chopin pieces included in the film. He spent several hours each day practicing because he felt that it was important for him to play those pieces on his own. 

But his method acting strategies didn't stop there. By the end of the film, Szpilman has been surviving on very little food for months, and he's starving. It's devastating stuff, and Brody would need to be noticeably thinner to accurately portray Szpilman after his time in the Warsaw Ghetto. Brody ended up losing 30 pounds for these scenes, getting down to 130 pounds. 

Although it was difficult, Brody insisted that this experience was necessary to play Szpilman. "There is an emptiness that comes with really starving that I hadn't experienced," Brody told the BBC. "I couldn't have acted that without knowing it. I've experienced loss, I've experienced sadness in my life, but I didn't know the desperation that comes with hunger."

Original source: https://www.looper.com/163803/why-adrien-brody-was-never-the-same-after-the-pianist/