(LOS ANGELES) -- Spoiler alert -- American Idol executive producer Nigel Lythgoe just told Ryan Seacrest that Wednesday night's show will feature the first-ever performance of a Nirvana song on Idol. Lythgoe said that Casey Abrams, who missed last week's results show due to illness, will perform the band's signature hit "Smells Like Teen Spirit." The theme for the show Wednesday night is "Songs from the Year You Were Born," and Casey was born in 1991, the year Nirvana became superstars.
Other spoilers for Wednesday's show: Lythgoe revealed that Thia Megia will sing Colors of the Wind from the 1995 movie Pocahontas.
And on Tuesday, Melissa Etheridge tweeted that one of her songs would also be performed, but she didn't say who would be singing what.
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