Justin Bieber Subs In for James Corden on 'Late Late Show'

Justin Bieber steps out on stage to take over for James Corden on The Late Late Show on Thursday (December 10) in Los Angeles.

The 21-year-old singer made a surprise appearance by opening the show with the monologue while James was still backstage getting ready. He ran out on stage in the middle of the monologue in his bathrobe and a towel wrapped around his head!

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James tried to kick Justin off the stage, but the audience erupted in boos. He then let Justin come back out and finish up the monologue. Watch below!