Saara's track for Saturday's live show was revealed on Good Morning Britain on Thursday morning, when Brian Friedman was on to talk about Fright Night.
We're not quite sure how 'Bad Romance' translates into a spooky Halloween weekend Fright Night song but we're guessing it will all be in the choreography and costume.
After the song choice was revealed by GMB, the Finnish singer tweeted: "Oh it's public! Yes I will be singing Bad Romance by @ladygaga! Are you guys excited??"
Saara Aalto (@saaraaalto) October 27, 2016
Saara was THRILLED last weekend when she made it through to week four without landing in the bottom two position again: she had to sing for survival in the first two weeks of the competition.
Show boss and judge Simon Cowell had advised that Saara, 29, needed to go a bit more bonkers with her performances and get a bit crazy on stage, which she did during last week's Divas and Legends Week, belting out an amazing rendition of Bjork's 'It's Oh So Quiet'.
The video has been viewed more than 1.6 million times on YouTube in just four days!
Meanwhile, we also know what Honey will be performing: she's gone for Will Smith's Men In Black theme song (aliens and monsters are pretty appropriate for Fright Night, right?) and will be showing off her singing skills as well as her usual rapping.
The rest of the song choices for the finalists are usually revealed on Friday.
X Factor continues 8pm on Saturday on ITV.
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