Katy Perry transported "E.T." to the "American Idol" stage Thursday (April 21) and even brought a special guest along with her: Kanye West.

The two reprised their recent #1 hit on the "Idol" stage in a pre-taped appearance during the "Idol" results show. The performance kicked off with Kanye's opening verse piped in via music video, so it was a surprise when the Coachella headliner appeared onstage with Perry later in the song.

Perry was carried on to the stage, arms outstretched, by three dancers dressed in alien getups, who hoisted Russell Brand's better half high above their heads. Perry was decked out in a white, form-fitting bodysuit tricked out with pink LED lights and a long white cape. She wore some sort of futuristic space crown atop her head, making her look like the queen of a far-off pop planet.

Green lasers crisscrossed the darkened "Idol" stage as Perry was placed into a throne-like cage, which was carted across the stage by her team of a half-dozen alien dancers.

West took the stage in a leather coat accented with a fur overlay and exercised self-censorship on his verse's "alien sex" line. West and Perry faced off at center stage, moving toward and away from each other to play up the tension between them. In the song's closing moments, Perry softly caressed West's cheek before retreating back to her throne, where the lights dimmed and her suit lit up with blinking, zigzagging lights.

Perry and West both have a history with "American Idol." [article id="1630557"]Perry chipped in as a guest judge[/article] during the early rounds in season nine, at one point threatening to throw a Coke in Kara DioGuardi's face, and performed "Waking Up in Vegas" -- in an Elvis jumpsuit, no less -- on the show during season eight. Earlier that same season, West took to the "Idol" stage to perform "Heartless," from his 808s and Heartbreak LP, which would later be transformed into a [article id="1611249"]winning performance by that season's champ, Kris Allen[/article].

What did you think of Perry and West's performance? Let us know in the comments!

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