It turns out platinum-selling recording artists struggle at karaoke sometimes, too!
Things get off to an especially terrifying start when Katy spins and lands on "Rain Is A Good Thing," one of Luke's songs. "I don't even know what that is," she says. Awkward!
Luke laughs it off, and Katy spins again. This time, she gets Shania Twain's "Man! I Feel Like A Woman!," and she's more than happy to give it a go.
After Katy gives us her version of the '90's country classic, it's Luke's turn to spin. He lands on the Bonnie Tyler karaoke classic "Total Eclipse of the Heart."
As most karaoke versions of the iconic power ballad go, it's a bit of a painful experience. Luke's voice cracks and he barely makes it through, but he ended the performance by shaking his butt. So, we're all winners.
Lionel Richie—the smartest man in the room for refusing to sing karaoke—welcomes Katy and Luke to the couch and the trio perform a version of his classic song "Endless Love."
They sound pretty good, which leads Katy to look at her microphone and ask, "Is there Auto-Tune in this?"
An Auto-Tuned microphone would have saved us from a lot of regrettable moments in college. Not a bad idea.
Katy, Luke and Lionel are in the middle of judging the latest batch of young music hopefuls on Idol's 20th season.
It remains to be seen if they will impart one of the greatest nuggets of wisdom for an up-and-coming performer: Stay away from "Total Eclipse of the Heart" at karaoke.
American Idol airs Sunday nights at 8 p.m. ET on ABC.