Alex & Sierra is an indie-pop duo who won the third and final season of the musical reality show "The X Factor USA" in 2013. They performed for the first time singing a version of "Toxic" (Britney Spears) and the performance was highly praised by the judges, being approved for the second phase, where they sang "You're the One that I Want" (John Travolta & Olivia) and went straight to the Lives Shows. In the live shows they sang several songs, they .
