Katy Perry

A source says Underwood was not producers' first choice.

This celeb was the top entertainer in 13 states, including Montana...

Surely that's not Luke's fault ... right?

Luke Bryan discusses Katy Perry's exit from American Idol, highlighting their ongoing and growing friendship.

After viewers criticized Katy Perry's comments, the contestant offered her perspective on social media.

He's the resident country expert on 'American Idol.'

Host Ryan Seacrest will also return for Season 21.