Carrie Underwood returning to 'American Idol' as surprise guest mentor

It's full circle for Carrie Underwood!

Sunday night's American Idol came with a special announcement -- the season four Idol winner would be returning to the show as a superstar guest mentor for this season's top five contestants.

The 35-year-old country crooner will also perform her latest single, "Cry Pretty," on the Idol stage, bringing her back to the place that started it all, 13 years later.

In the meantime, Gabby Barrett, Cade Foehner, Caleb Lee Hutchinson, Maddie Poppe and Michael J. Woodward are headed to Nashville, Tennessee, where they'll have a special mentoring session with the "Dirty Laundry" singer before putting their own spins on songs from her catalogue.

ET's Lauren Zima caught up with a few of the contestants backstage after Sunday's live broadcast to see how they were handling the news.

Pittsburgh, Pennsylvania, native Barrett told ET that she was jumping up and down onstage "like a flopping fish" when Underwood's involvement was announced. "I'm wearing heels right now and I didn't even know I could jump in these heels," she joked.

"I had to fight back tears, I really had to, because [Underwood] is just somebody that I've looked up to my entire life," the 18-year-old singer added. "Ever since she won on American Idol I've just really watched her grow as a person, and her family, and how she sings and how she acts and just everything about her. So, I'm gonna freak out when I meet her and probably gonna cry."

As for Foehner, he's looking to get some practical tips. "Shoot, first I want to pick her brain how she survived this," he said. "Next, I want to figure out how I can take her song and make it my own with respect to her. 'Cause I love her catalogue and I want to pay dues to it."

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