Derek watches in hilarious embarrassment as Julianne makes her way onstage to lip-sync maybe the raunchiest song the show has ever seen, "I Just Had Sex" by The Lonely Island.
Of course, her song choice is paired with some musically timed gyrations. And you know they're spot-on since Julianne is a trained dancer.
The cherry on top is Derek's expressions, which perfectly capture any brother's reaction to watching his younger sister sing about sex and penises on stage.
"It felt so good when I did it with my penis," Julianne mouths with some rather suggestive gestures at her crotch.
Derek finally has enough and covers his eyes.
Even cohost Chrissy Teigen can't quite get her jaw to close as she laughs in surprise at the performance and brings a hand to her chest.
The shirtless dancers also do wonders to make the performance even more of a shock-fest, especially with the way they hump the floor.
If the goal is to completely embarrass your competition, then Julianne is for sure the winner of this one.
Of course, we recommend you keep your mind open and enjoy this fantastically awkward sneak peek at the upcoming episode. Clearly, Julianne is a confident lady to belt out a tune like that in front of family.
This is far from the first laugh-out-loud-worthy lip-sync battle we've seen. Anne Hathaway went all out for her rendition of "Wrecking Ball" by Miley Cyrus. Dwayne Johnson bared his heart with "Shake It Off" by Taylor Swift. And John Krasinski channeled his inner boy band with "Bye Bye Bye" by *NSYNC.
Check out Julianne Hough's full performance this Thursday during Lip Sync Battle on Spike.
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