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West contributes two verses to the song -- the fourth single off Perry's platinum selling 'Teenage Dream' -- and also cameos in the cosmic video, released at the end of March. However, Perry's performance last night during the weekly 'Idol' elimination show -- wild card Stefano Langone was shown the door -- opened with Kanye's clip from the music video, suggesting that he was not present.
Perry performed the track dressed like a space alien queen, with backup dancers dressed like the extraterrestrials she sings about in the song. West sauntered on for his closing verses wearing a burly fur vest. The guest appearance comes as a surprise, especially after Perry was spotted at the Coachella music festival, where West was a headliner and performed a snippet of the track without her.
Kanye last appeared on 'American Idol' in 2009 where her performed 'Heartless.' 'American Idol' season seven winner David Cook also performed on the show Thursday evening.
Watch Kanye and Katy Perry Perform 'E.T.'