Who Says Justin Bieber Is 'The Most Loyal Person' He Knows?

Justin Bieber's red carpet appearance at the Believe world premiere was brief, but his celeb friends did all of the talking as they came out to support their buddy on his big night.

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"Justin is a dear, dear friend of mine," says Mike Posner, who appears in the flick and co-wrote the Biebs' hit "Boyfriend." "He’s one of the most loyal people I know, definitely one of the most loyal artists I know. Anything I need he would do it for me. When he asked me to be a part of this film of course I said yes and of course I’d be here to support him."

Director Jon M. Chu says fans can expect to see a different side of the singer since his first flick, Never Say Never.

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"The movie changed throughout the whole year as he was changing and so when we started to realize that this was one of the most significant years of his life thus far we knew we had a really interesting story to tell," says Jon. "All of the different events that happened and seeing how stories would get spun out of control and we were there and we know that wasn’t the truth. Just seeing him as a human being was really important because I’m a huge fan of pop culture but the more we try to see him as an object and try to tear him down for fun and entertainment I think is unfair."

Believe opens in theaters on Christmas Day.

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