NEW YORK (CNN) -- Emmy Rossum got off to a quick start as a singer. At the tender age of 7, she joined the Metropolitan Opera's Children's Chorus. Now, at 15, she's graduated to motion pictures, with a featured role in "Songcatcher." The film, about the deeply rooted peoples of Appalachia and the origins of country music, got a rousing reception at the Sundance Film Festival and is just now getting a national release

CNN: Did you ever expect your musical career to translate into a movie career?

Emmy Rossum:: No, not really, actually. I grew up in New York City and I used to go to the Spence School. I think my mom put me into music programs when I was really young, from like the time I was about 2 years old, because she sings about as well as my shoe. She was really hoping that I could maybe sing a little, so she put me into music programs, and then I was in the chorus at school. Then the chorus director told my mom that I had perfect intonation, and that she should take me to audition for the Metropolitan Opera's Children's Chorus.

CNN: What does a 7-year-old child's audition entail?

Rossum:: They told me to do prepare some songs, so I decided to prepare the songs that I learned in the chorus at Spence. I did "Jingle Bells" and a Hanukkah song. I had all the bases covered. But I got there and she said, "No, I don't want to hear anything that you've prepared" -- of course. She had me sing "Happy Birthday" in different keys to check my intonation. And when I was done singing she said, "Welcome to the Opera.

CNN: Do you find acting to be a natural transition for you?

Rossum:: Definitely. So much of a part of what we did on stage here was acting. I was so well trained from being here. We sang in German, French, Italian, English, Russian. All the dialect training I got here, I used in "Songcatcher." Here we were trained, and we had to compete for the parts, and there was rejection.

The first time that I got to a set, which was "As the World Turns," I said to my mom, "God, it's so small. Where are all the animals and the horses and the donkeys?" Because I worked with Franco Zefferelli where he did these huge magnificent performances of "Carmen" and ... "A Midsummer Night's Dream." ... Where are the 4,000 extras and horses and donkeys?

CNN: How did you make the leap from performing exclusively music, to carrying one of the lead roles in a film?

Rossum:: I'd been acting about a year and a half or auditioning and stuff. And after I left the opera, I got an agent. I started going out on auditions and I did a really brief recurring role on "As the World Turns," as the long-lost biological daughter of Holden and Molly. Then I did a "Law and Order," and I did a couple of miniseries and TV movies -- one with Marisa Tomei, where I played her daughter, and one playing the young Audrey Hepburn.

Rossum:: Yes. I guess what the story is really about is love and music and the opportunities that came about for women at the turn of the last century. I play a young girl in the mountains who is an orphan and who is really hopeful and eager to learn, but she doesn't have many opportunities because she's in this little village in the middle of nowhere -- until this independent woman, this musicologist, comes to Appalachia and discovers this little girl's music and (the) ballads that have been passed down to her through oral tradition from her grandmother.

CNN: Would you describe the story of this film as the birth of country music?

Rossum:: Well, it's basically how country music originated. And most people don't know this, but country music originated from ballads -- Scotch-Irish ballads that were sung in the 1600s by the people who came over to America and settled in Appalachia.

There was so much feeling in the music, and I really hope through this movie that the music can stay alive because it is so beautiful, and it's going to die out if we don't help it.

CNN: You have a duet with Dolly Parton on the soundtrack, written especially for this film.

Rossum:: Yeah, somehow Dolly saw "Songcatcher" after the producers asked her if she might be interested in doing a song on the soundtrack and she said, "Wow, I'd really like to write a duet for me and this girl who's in the movie to sing." She flew me out there, and we recorded it, and it's like a mother/daughter duet about a girl who wants to run off and get married.

CNN: In addition to everything else, this movie has won this year's Sundance Film Festival's Best Ensemble award. Were you at the festival in Utah?

Rossum:: Yes, it was amazing. I had never been to Sundance before and I have never seen so many Los Angeles people on cell phones in a one-block radius, because this town (Park City, Utah) is so small. When we won, the director called me up on stage and said, "Emmy say something," and I was like, "Uhhh, hi!"

It was so much fun and I was so thrilled.

CNN: You're still in high school. Where do you study?

Rossum:: Well, I am home-schooled with tutors and I also take classes online through Stanford University. They give high school courses for gifted high school students online. There is a teacher in the room and a virtual blackboard and you can write on it, and the teacher writes on it and you talk about books and whatever the assignment was. And you press control/spacebar to raise your hand.

Rossum:: I just finished a movie actually for the BBC earlier this year. It's a very sophisticated thriller/horror (movie) where I am actually playing two characters who strongly resemble one another. And right now I am working on Dan Ireland's new film, "Passionata." It's about a 17-year-old Portuguese girl who wants to be a professional gambler and she is willing to fix her mom up on a date with this professional gambler in exchange for some gambling lessons. And she's a bit naive and she gets into some trouble. So let's just leave it at that. But it's a comedy.

CNN: Let's talk big picture. You're only 15 years old. Where would you like to see your career go?

Rossum:: Gosh, I just hope that I am always doing good work, and that I am having fun. I love Brenda Blethyn and Julia Roberts.

CNN: So you'd like to be a cross between Brenda Blethyn and Julia Roberts.

Rossum:: Exactly, and just as long as I am having fun and doing good work -- and I am able to say that I am proud of what I do, and that I am doing stuff that people enjoy.