Nathaniel was someone disconcerted to find the door to his box shut and even more annoyed to find it locked. Box tickets were always more expensive than regular seating, and doubly so when bought at the last minute. To arrive at his box and find it locked - likely to keep people from switching to better seats mid-way through - rated slightly higher on his scale than mere 'annoyance'. It meant he was going to miss the opening of the whole production just so he could sit in the seat he paid for. Simply because he arrived a tad late due to traffic did not mean his box should be locked.
Decidedly not in a favorable mood, he sought out one of the ushers and promptly demanded they unlock his seat so he could attempt to salvage the evening and perhaps enjoy a moment of the show. They were lucky he'd seen it before and was familiar with the opening.
The usher was, of course, understanding of his ire, and moved quickly to attempt to fix the situation. It was only after his key turned in the lock and the door didn't open that the man grew worried. A stuck door did no one any good. Least of all the Opera House and a very rick looking and steadily growing angrier patron. The usher apologized and attempted to push the door in, throwing his shoulder against just hard enough to make it budge (normally) and not make a sound loud enough to disrupt the show for those watching in the seats beyond and below.