Casey Bishop put away the rock ‘n’ roll for something classic this week.

On Sunday’s “American Idol”, the 16-year-old performed a rousing rendition of Judy Garland’s “Over the Rainbow” from “The Wizard of Oz”.

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The young singer immediately captured the judges’ attention with her incredible vocals, slowly building the song to a dramatic, powerhouse conclusion.

“You can do anything you want!” Katy Perry remarked after the song was over. “You can sing rock, you can sing R&B, you can sing standards, you can sing Judy Garland. It’s all inside of you, and it’s so beautiful.”

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Lionel Richie added, “I keep looking down at 16, wondering what the heck the DNA is made of. Because you are hell under pressure. … You’re controlling every facet of your delivery. Rock to ‘Somewhere Over the Rainbow’. It’s just unbelievable.”

The audience agreed with the judges, sending Bishop right through to the Top 10.