“American Idol” judge Carrie Underwood has surprised viewers with a callback to her time on the show in 2005.

Days after she shared a 20-year-old clip of her performing Heart’s hit 'Alone,' she opened the show’s Rock and Roll Hall of Fame special with the song

There were enough hints dropped by American Idol regarding this nostalgic performance, but still, it took fans by surprise. Carrie Underwood, who first appeared on the stage 20 years ago as a contestant,