The much-anticipated lineup for the live two-night American Idol finale starting on Sunday (May 20) is, of course, completely star-studded, with performances from judges Luke Bryan, Katy Perry and Lionel Richie all on tap ... as well as another special guest country fans will be sure to love: Darius Rucker.

"Y’all know this is going to be a good time!" Rucker exclaims on social media, posting the finale's full lineup for fans to check out. Other performers for the evening include Gary Clark Jr., Nick Jonas and Mustard, Bebe Rexha, Patti LaBelle, Yolanda Adams ... and Kermit the Frog. Yes, really!

The two-part season finale will pit the top three contestants, Caleb Lee Hutchinson, Gabby Barrett and Maddie Poppe, against each other for the ultimate title (no word on whom Kermit is voting for).

Rucker will perform on the second night, May 21, and it isn't the first time he's taken the Idol stage. Rucker also performed on the 2014 season finale singing "True Believers," which is the title track of his 2013 studio album.

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