'Inside Llewyn Davis' Star Oscar Isaac on Working in Film vs. Music (Video)

"They're both tough because you're dependent on the whim of the gatekeepers, those people who are going to let you in," says the actor, who plays a struggling folk singer in the Coen brothers movie.

Oscar Isaac has the unique perspective of having worked in both the film and music worlds, which makes him the perfect actor to take on the titular role in the Coen brothers' Inside Llewyn Davis.

In the film, Isaac, who was in a punk band growing up that once opened for Green Day, plays an aspiring folk singer in the 1960s. He did all of his singing live for the film, which puts on display his undeniable musical talents, as well as his leading-man abilities.

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A graduate of Juilliard whose previous acting roles include Drive, Isaac tells THR that the fields of music and film are both difficult on artists.

"They're both tough because you're kind of dependent on the whim of the gatekeepers, those people who are going to let you in," he says. "There's no real objective view of what's good and what's not -- you're dependent on their opinions."

But he adds that music is probably a tougher career ambition. "Especially for people who write music, because it's such a personal thing, and to have that rejected can be really rough," he adds.

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THR also spoke to the stars of the film about what song would be on the soundtrack for their own life:

Oscar Isaac: "Inner City Blues" from Marvin Gaye's What's Going On. "Maybe it's similar to the Coens. It's both melancholy and groovy at the same time. There's a contradiction in the music that I like."

John Goodman: "I Was Young When I Left Home" by Bob Dylan. "We did a concert at Town Hall in New York about a month ago, a month and a half ago, and one of the songs that Marcus Mumford sang … I can't get it out of my head since then. It just haunts me."

Stark Sands: "You Make My Dreams Come True" by Hall & Oates. "[It's] the song I danced my first dance with my wife."

T Bone Burnett: "500 Miles" by Hedy West (which is featured in the film and included on the Inside Llewyn Davis soundtrack). "That song is so much about the United States. Everything about the United States is about that dislocation -- seven, eight nations coming together here to form a new community, a new people and what does that mean. I think everybody who has come to this country has that in his genetic makeup."

Inside Llewyn Davis opens in theaters in Los Angeles and New York on Dec. 6, and nationwide on Dec. 20.

Watch THR's interview above.

Email: Rebecca.Ford@THR.com
Twitter: @Beccamford