There's only one thing better than seeing our favorite celebs cut a rug on 'Dancing With the Stars' -- and that's when Jessie J stops by to guest judge!

During last night's (Oct. 13) episode, the 'Burnin' Up' singer stopped by to score the dancers and even performed 'Bang Bang' and 'Masterpiece.' It goes without saying that Jessie J slayed her songs, but we totally loved her judging comments as well!

Numerous times throughout the evening, the singer admitted she reacted as an observer, not a pro with technical feedback, but she still gave tons of insightful critiques and showed off her sense of humor.

As for the dances themselves, this week's episode featured the notorious switch-up, which meant the stars were paired with different pros. At the end of the evening, 'Duck Dynasty star' Sadie Robertson earned the top score.

No elimination last night, which means next week will have even more suspense! In the meantime, check out Jessie J performing 'Bang Bang' in the video above and 'Masterpiece' in the video below!

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