Katy Perry hits 'American Idol' stage with 'E.T.'

katy-perry-idol-gi.jpg Katy Perry is set to appear on "American Idol" next week, joining past winner David Cook on Thursday's (April 21) results show.

Perry will perform "E.T.," the latest single from her album "Teenage Dream." It will be her third appearance on the show and her second time performing: She sang on the Top 3 results show in Season 8, when she wore a cape emblazoned with Adam Lambert's name, and was a guest judge during the audition round last year.

"E.T." (featuring Kanye West) is in its third week at No. 1 on the Billboard Hot 100 chart. It's the fourth song from "Teenage Dream" to reach the top of the charts. If West is joining her on the "Idol" stage Thursday, FOX is keeping it under wraps.

We'll also be curious to see if Perry wears anything declaring her favorite in this season's competition.

Season 7 winner Cook, meanwhile, will perform his new song "The Last Goodbye" on Thursday.

Photo/Video credit: Getty Images