《美国达人》(America’s Got Talent)S08E20<br>TWELVE SEMI-FINAL ACTS PERFORM LIVE FOR AMERICA’S VOTE AT THE WORLD FAMOUS RADIO CITY MUSIC HALL The first 12 semi-finalists perform live at the legendary Radio City Music Hall for the chance to win one million dollars and become the most talented act in America. Howard Stern, Mel B, Heidi Klum and Howie Mandel star as the celebrity panel of judges and Nick Cannon hosts.<br><br><br>