The new musical Hamilton doesn't open officially on Broadway until August 6, but celebrities are already flocking to Lin-Manuel's hip-hop history lesson. A slew of stars were in the crowd on July 29, 2015, including Billy Crystal, Whoopi Goldberg, Alex Trebek, Alicia Silverstone, Gayle King, and Questlove. After the show, the cast invited the stars onstage for a group photo. Check out these Hot…
