Perhaps Gyllenhall is all of those things, and more — it’s hard to describe an actor who often stars in films like Life that open in thousands of theaters as well as films that open in one.

That “preparation” often includes significant changes in his body, whether it was bulking up for Prince of Persia and Southpaw or slimming down for Nightcrawler. It’s an aspect that Gyllenhaal and his sister, actress Maggie Gyllenhaal, disagree on. He reveals, “My sister and I have this argument often. I’ve lost weight or learned a new skill and she’s said: ‘You don’t have to change your body to play a character,’ and there are times where I agree and other times I don’t.”

One of the reasons why Gyllenhaal feels it is necessary is because it helps in the creation and understanding of a character. Gyllenhaal explains, “It seems to me that anybody feels they can be an actor nowadays… People say: ‘How hard can it be?’ But the truth is, the creation of a character, the understanding of human behavior, is a craft and to be learned and worked and experimented with and discovered. My favorite actors are like artists, and when you see their career, you see someone who is able to actually physically draw a perfect figure and then deconstruct it, or not, based on a foundation of skill or practice. Whereas I noticed that some people just throw some paint up on the wall and call it art.”

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