Find a chorus member, tell them how great they are, and how you saw them in something else and how amazing of a performer that they are, blah blah blah, tell them that you'd like to meet them after the show....sucking up always helps...
Actually, I'm kidding....Unless you have a reason to be backstage, (know a performer, musician, etc.) then don't try to push your luck, see the show, go home, review it on here and sleep tight.
I adore the black band holding on the Phantom's mask. ~ Jenna2