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Justin Bieber, 1D, Iggy Azalea Join James Corden for All-Star Christmas ‘Carpool Karaoke’ (Video)

Reggie Watts helps kick off montage featuring all prior guests of the popular ”Late Late Show“ segment — besides Mariah Carey

James Corden has one last Christmas surprise for all the “Late Late Show” viewers who have been good boys and girls this year.

The CBS host unveiled a mash-up on Thursday night featuring most of his “Carpool Karaoke” guests singing an upbeat version of “Joy to the World.”

Reggie Watts joined him “live” in the Range Rover to set up and carry out the montage, but the final edited video cut featured the band leader, One Direction, Justin Bieber, Carrie Underwood, Rod Stewart, Stevie Wonder, Iggy Azalea and Jason Derulo.

Derulo was a tad too cool for school at first, but even he got into the holiday spirit by the end. For her part, Azalea dropped a handful of freestyle Christmas rap bars, which will probably just fuel the recent and popular criticism of her emcee skills.

The glaring omission from the compilation was Mariah Carey, who feels synonymous with Christmas music thanks mostly to her massive hit, “All I Want for Christmas.” Carey may have been left out simply because she was the first “Carpool Karaoke” guest, and the idea for the collection perhaps came around after the segment became a hit.

Watch the video above.