Sia, is that you? Kelly Clarkson got into the Halloween spirit a few days early during a Facebook Live session on Friday, October 28, as she sang an amazing a cappella cover of Sia's "Chandelier" while wearing the singer's signature blonde wig.

"Welcome! Hey, what's up? I'm Sia this Halloween," the 34-year-old announced in the video, which was filmed inside the greenhouse of her Nashville mansion. "She's one of my favorites, so I thought I'd wear a wig and be Sia. I'm gonna cover a Sia song here real quick, and then I'm gonna talk to you.… Here you go, Sia. I hope you like it."

Clarkson then launched into an incredible rendition of the Grammy-nominated 2014 song, effortlessly nailing every note.

After the performance, the American Idol season 1 winner joked, "I don't know how she does this because, you know, she can't see. But it's also kind of awesome because you're in your own little world when you're performing. I love that song — everybody loves that song!"

As fans know, Sia often dons an oversize blonde wig (among other disguises) during her public appearances and performances. She explained in an October 2013 Billboard op-ed titled "My Anti-Fame Manifesto" that she obscures her face because she hates the idea of fame and prefers to stay out of the spotlight.

"If anyone besides famous people knew what it was like to be a famous person, they would never want to be famous," the Australian singer-songwriter (born Sia Furler) wrote. "Imagine the stereotypical highly opinionated, completely uninformed mother-in-law character and apply it to every teenager with a computer in the entire world. Then add in all bored people, as well as people whose job it is to report on celebrities. Then, picture that creature, that force, criticizing you for an hour straight once a day, every day, day after day."

Watch Clarkson's flawless cover of Sia's "Chandelier" above!

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