Two of American Idol's most successful winners are returning to the series for its final showdown.

On Friday, Rolling Stone announced that Season 1 winner Kelly Clarkson and Season 4 winner Carrie Underwood are set to perform on the finale airing on Thursday, April 7.

It wasn't mentioned what songs they would be singing, but odds are likely that fans can expect something emotional and beautiful.

Adam Lambert, who came in at second place on the show in Season 8, previously performed his latest single "Welcome to the Show." In a report from Entertainment Weekly, the superstar explained how he wanted to give the audience something worth remembering and how he received help from people who worked with him on the song.

"I wanted to surprise my fans with a new, uplifting anthem for our spring," Lambert said in a release. "I asked Max Martin for help and he paired me up with two great writers and producers; Ali Payami, who worked with me on 'Ghost Town,' and Swedish star Laleh who is also a featured vocalist on the track. I feel this song will give people strength to be exactly who they are."

The remaining contestants on the final season are La'Porsha Renae, Mackenzie Bourg, Dalton Rapattoni and Trent Harmon. The last episode bid its farewell to Sonika Vaid after she sang "Let It Go" from Disney's Frozen.

American Idol airs on Thursdays at 8 p.m. ET on FOX.

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