The competition heats up as the top 24 "American Idol" hopefuls return to Hollywood for a shocking night of reveals. Last week's votes are in and season 20's Top 20, hand-picked by America, will be revealed. All 20 remaining contestants will perform for superstar judges Luke Bryan, Katy Perry and Lionel Richie, and viewers at home will vote once again to determine who will make it to the next round.