James Corden and Reggie Watts kick off a Christmas edition of Carpool Karaoke singing "Joy to the World" with One Direction, Stevie Wonder, Iggy Azalea, Rod Stewart, Carrie Underwood, Jason Derulo and Justin Bieber. Subscribe To "The Late Late Show" Channel HERE: http://bit.ly/CordenYouTube Watch Full Episodes of "The Late Late Show" HERE: http://bit.ly/1ENyPw4 Like "The Late Late Show" on Facebook HERE: http://on.fb.me/19PIHLC Follow "The Late Late Show" on Twitter HERE: http://bit.ly/1Iv0q6k Follow "The Late Late Show" on Google+ HERE: http://bit.ly/1N8a4OU Watch The Late Late Show with James Corden weeknights at 12:35 AM ET/11:35 PM CT. Only on CBS. Get the CBS app for iPhone & iPad! Click HERE: http://bit.ly/12rLxge Get new episodes of shows you love across devices the next day, stream live TV, and watch full seasons of CBS fan favorites anytime, anywhere with CBS All Access. Try it free! http://bit.ly/1OQA29B