You already know that Little Mix walked away with the championship on this week's season finale of the U.K. version of 'X Factor.' However, that wasn't all that went on during the show -- in fact, a star-studded lineup of performers appeared to send the season off in style, including Leona Lewis and Coldplay.

Lewis offered up a live rendition of Nine Inch Nails' 'Hurt,' which is one of the covers she recorded for her recently released EP of the same name, while Coldplay performed a pair of tracks from their new album, 'Mylo Xyloto.' You can check out the amazing performances below.

Lewis, of course, is an 'X Factor' alumnus, having won the third season back in 2006. She's since gone on to sell more than 10 million albums worldwide, but she hasn't forgotten where she came from, and it's nice to see her paying tribute to the show that sparked her career -- even if this version of 'Hurt' probably won't make you forget the original (or Johnny Cash's unforgettable cover).

Coldplay is staying busy on the promotional trail, ensuring that sales stay strong for the chart-topping 'Mylo Xyloto' by offering up this blend of the album's last single ('Paradise') with their upcoming single for January 2012 ('Charlie Brown').

Meanwhile, the American 'X Factor' is wrapping up its first season, with the semifinal round scheduled to kick off tomorrow (Dec. 14).

Watch Leona Lewis Perform 'Hurt' on 'X Factor' in the U.K.

Watch Coldplay Perform 'Charlie Brown' and 'Paradise' on 'X Factor' in the U.K.