"I can't believe that it's finally here. I'm so excited," she told Access Hollywood, adding that she had only seen the "rough draft" of the movie before the premiere.
"I think that makes it even more exciting, that I haven't [gotten] to see everything," she said.
Miley flew solo on the red carpet, but she said boyfriend Justin Gaston was in attendance.
"My boyfriend? He's here," she said. "He just wanted tonight to be my special night."
And the young star confirmed that she was happily in love.
"Yeah and you know, it's cool," she said.
"She is just so undeniably 100 percent Miley all the time," he said. "She is Miley wherever she goes, even if we're at the house, she's still Miley. With or without the wig, she's still funny."
As her "Hannah" co-star, as well as her father, it's Billy Ray who has had to do some juggling.
"I try to balance life and best as I can. I balance being a daddy, being her acting partner, her singing, songwriting partner," he said. "But most of all, we try to be friends and live, love and laugh as much as we can — we're gonna try to do it all tonight."
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