Demi Lovato and Olly Murs suited up for their performance of 'Up' on the Season 11 finale of 'X Factor UK' last night (Dec. 14), delivering a heartfelt number while dressed to the nines.

While we've been loving the duo's collab ever since we first heard it, there is always something to be said for a live performance -- there's just an undeniable energy that comes across when an artist gets in front of an audience. And you can tell that Demi and Olly had it goin' on, singing their hearts out and playing off one another in the live duet. (We're also totally digging their ensembles, with Olly's relaxed-yet-formal suit and Demi's totally glam updo and off-the-shoulder gown.)

And though we've watched Demi kill it on stage time and time again, we don't think we'll ever stop being amazed by the genuine emotion that she pours into each performance, belting out each note with more feeling than the last. She slays it every time!

Check out Demi Lovato and Olly Murs' performance of 'Up' in the video above!

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