The season 2 stars performed alongside the season 21 finalists.
Jelly Roll chats with ET's Denny Directo at the live finale of 'American Idol,' which aired Sunday on ABC.
The 'Idol' judge opened up to ET after Sunday's powerhouse season 21 finale!
See which of the final contestants took home the victory Sunday night.
Chilli and T-Boz of TLC chat with ET's Denny Directo at the live finale of 'American Idol,' which aired Sunday on ABC.
Ryan Seacrest chats with ET about the 10th anniversary of his foundation's Seacrest Studios at Children's Hospital of Orange County.
The former daytime host will be back as a guest to promote 'American Idol.'
Katy Perry shared a GRWM video to Instagram on Monday with a little help from fellow ‘American Idol’ judge Luke Bryan.
Lionel Richie chats with ET's Denny Directo after 'American Idol's Disney night live taping. 'American Idol' airs Sundays on ABC.
The longtime host is gearing up for the show's season 21 finale.
The singer and 'Idol' judge opened up to ET on the carpet following Sunday's new 'Disney Night' episode.
The singer spoke with ET on Sunday for 'Idol' Disney Week.
Katy Perry chats with ET's Denny Directo on Sunday after 'American Idol's live Disney night episode, which aired on ABC.
The country crooner was a judge on 'Idol' from seasons 12-15.
