Joaquin Phoenix

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Before his role as Johnny Cash, Joaquin didn't even sing in the shower. "Singing was completely foreign to me," he says, "so was playing the guitar. But we had a lot of help. ... Obviously it was something that I was really nervous about. I have a great deal of respect for singers. It's really vulnerable going out in front of a crowd and singing—but then to sing like these characters who were so well known and had such distinct voices and were so loved—it was a great challenge. ... The nice thing was we weren't really result oriented. It was about working through the music. Getting to know the music, getting to know the lyrics. 'What was John trying to say?' as opposed to just, 'Let's try and sound like John.'"