Mila Kunis plays an addict in Rodrigo Garcia’s “Four Good Days,” and to play the part, she had to lose an extraordinary amount of weight and watch a lot of YouTube videos.

“I don’t know [how much weight I lost] because I don’t have a weight scale but I can tell you, based on my clothing, I was as thin as I was for ‘Black Swan,” Kunis told TheWrap’s Beatrice Verhoeven at the Sundance Film Festival. “I was healthy in regards to the way I did it but as far as a lifestyle choice, I was like, ‘Oh this is rough.’ But it only had to be for a minute. You have to unfortunately look a certain way to look like a heroin addict so I think I did it over four months. I exercised and dieted. I felt very strong… but I was thin.”

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