Carrie Underwood's iconic performance of 'Alone' after 20 years. Underwood memorably sang "Alone" on "American Idol" in 2005, delivering what fans consider to be one of the greatest performances ...

Carrie Underwood opened the latest episode of American Idol on Sunday, April 27, with a cover of Heart's "Alone," and fans say she "took the season by storm" with the nostalgic performance.