returns Wednesday night, and ET is following along throughout the hour-long episode to break down all the biggest and most surprising moments from the fourth and final exciting night of results from the season 15 quarterfinals.The show's panel of judges — including Howie Mandel, Sofia Vergara and Heidi Klum — and host Terry Crews will preside over the show as America finds out who will be moving on to the semifinals, and who will get sent packing.Out of 11 acts, only five will get to keep their