Music·Posted on Sep 30, 2019Confused As To How Billie Eilish Pulled Off That "Saturday Night Live" Performance? Let Us Explain.Spoiler: It's an illusion.by Ryan SchocketBuzzFeed StaffLinkFacebookPinterestTwitterMail You probably have seen that singer Billie Eilish was the musical guest on Saturday Night Live this week. View this photo on Instagram She sang a beautiful rendition of "I Love You" and gave a gravity-defying performance of "Bad Guy." View this video on YouTube youtube.com In the performance, she crawled around on the ceiling: Tap to play GIF Tap to play GIF And danced on the walls: View this photo on Instagram A lot of people wondered how the hell she did that. Elia Penn @EliaPenn How she did it #BillieEilish #SNL 04:10 AM - 29 Sep 2019 Reply Retweet Favorite De-Aged De Niro @yosoymichael Wait, how the fuck did Billie Eilish do this “Bad Guy” performance on SNL? She’s literally walking around a box? 07:49 PM - 29 Sep 2019 Reply Retweet Favorite Max Weiss @maxthegirl Okay someone’s going to need to explain to me how Billie Eilish did that box thing. 11:58 AM - 29 Sep 2019 Reply Retweet Favorite Brad Galli @BradGalli How did Billie Eilish do this on SNL? 04:30 AM - 29 Sep 2019 Reply Retweet Favorite Well, Justin Theroux — who was in the audience — shared a behind-the-scenes look at the performance, which showed how it worked: Tamara @yogurtgarol Thank you, Justin Theroux's IG for a glimpse of how they did this Billie Eilish performance #SNL 04:12 PM - 29 Sep 2019 Reply Retweet Favorite Instagram: @https://www.instagram.com/justintheroux/?hl=en As you can see in the video, the stage itself moves throughout the performance. Tap to play GIF Tap to play GIF The camera that films that performance moves along with the stage, which creates the illusion that Billie's walking on the ceiling and shit. In other words, when Billie's walking on the "ceiling," she's really just walking on a floor that looks like it's the ceiling. Amazing, right? Tap to play GIF Tap to play GIF Bravo, Billie! Seriously, that performance was badass. Tap to play GIF Tap to play GIF