Sia and her weird giant bow wig join James Corden for 'Carpool Karaoke' (Video)

Sia joined James Corden for a surprisingly deep and especially all-over-the-place "Carpool Karaoke" on Tuesday night.

In addition to powerfully belting out the Aussie pop star's hits, the Range Rover duo talked alien evidence, labeled wigs "head-hugs," and proved Sia's ability to hold a dozen eggs in both hands — sans carton, of course.

But first, the perpetually face-cloaked singer opened up about her real reason for all the crazy wigs and disguises. If you don't know Sia's story, it may change your mind about the talent behind "Diamonds" and "Chandelier."

"I don't wear this unless there's cameras around," Sia explained. "I only wear this just to try and maintain a modicum of privacy."

Also Read:James Corden Berates Justin Bieber in Carpool Karaoke After Grammys (Video)

"I was a singer already for like 10 or 11 years to mediocre success," she continued. "I was an alcoholic and a drug addict. And I sobered up and decided I didn't want to be an artist anymore, because I was starting to get a little bit famous and it was destabilizing in some ways."

So, for her triumphant return, Sia decided to bring mystery to pop music: "There's pictures of everyone on Instagram at the dentist," she explained to an understanding and appreciative "Late Late Show" host, who soon donned a similar hairpiece.

Watch the video above, which also proves that Sia has a surprisingly strong sense of humor.

Check out more from Sia in the video below!

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