Alex & Sierra performed their unplugged song “Say Something” by A Great Big World feat Christina Aguilera on The X Factor USA Season 3 top 6 performance show, Wednesday night, December 4.
Simon Cowell: My favorite performance of the season.
Paulina Rubio: I’m impressed.
Kelly Rowland: I thought I saw a performance on an awards show.
Demi Lovato: You two playing instruments was magical.
Watch the video below.