American Idol judges noticed something different when Laine Hardy performed Elton John's "Something About the Way You Look Tonight" on Sunday night (May 12).

Actually, Katy Perry, Luke Bryan and Lionel Richie noticed a few things were different, and they liked it.

Hardy performed the song without his guitar, making his classic rock cover as much of a vocal showcase as he's ever had. The 18-year-old from Louisiana wore a shimmering silver suit and sang the song with a patient, smokey delivery.

"Laine, did you like go to a voice coach or something?" Perry asked when he was done. Hardy admitted that he had, to which the pop singer replied that it showed.

"You've pushed yourself. You've challenged yourself and it's paying off," she remarks in the above clip.

"You've got this gravely thing that's your signature but we heard you singing tonight, which was really amazing," Bryan adds.

Watch: Who Is Laine Hardy? 

"I've got only question," Richie begins: "Have you been in my closet? Because I'm telling you you're crossing the line now, son."

Additionally, Hardy performed the Beatles' "Hey Jude" and Marshall Tucker Band's "Can't You See," but he kept his guitar on for those two songs. The response from the three American Idol judges was again positive, but no one offered any sort of specific critique. Hardy moved onto the finals, where he'll be joined by Alejandro Aranda and Madison VanDenburg.

The season finale of American Idol on ABC is May 19. It's not clear what the 2019 winner will get, but 2018 winner Maddie Poppe won a recording contract worth $250,000.

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