Beckett Rex Quits ‘American Idol’ In Third DNyuzAmerican is the beloved vocalist who mesmerized thousands of fans with his noteworthy talent on the popular singing competition. Beckett stole spectators across the nation with his spellbinding vocals and charismatic stage presence. His choice to leave American Idol stunned the entire audience, leaving his fans crushed. However, Rex will always be remembered as an inspiration in the history of American Idol.