Susan Boyle

It took one song to turn Susan Boyle from a bashful woman in a housedress into an internationally renowned superstar. The Scottish singer became an overnight sensation after her moving performance of the "Les Miserables" standard, "I Dreamed a Dream" on the reality competition series "Britain's Got Talent" (ITV, 2007- ) surprised the show's audience and judges, including the hard-to-impress Simon Cowell. Boyle suddenly became an international phenomenon after the clip went viral on sites, but her rapid rise to fame took an emotional and mental toll on the singer. She checked herself in to a private psychiatric clinic in London the day after she placed second on the "Britain's Got Talent" finale. After battling exhaustion and a near-mental breakdown, Boyle finally released her chart-topping debut album in November 2009, appeared stateside by giving high profile interviews to Larry King and Oprah Winfrey, and defied the odds to be called one of the most naturally gifted vocalists of her time.