In college, we entered theater from a downpour, with no plan of what to see. Had no idea what Diggstown was, spent much of the movie's first hour wondering if we had made a mistake. Then Lou Gossett began boxing guys, and by the end, we were all cheering our lungs out. A total surprise.
Blair Witch in a packed theater in Austin, and you could hear the proverbial pin drop. Also: pacing back & forth at the back of the theater playing Milagro Beanfield while in labor w my daughter, not wanting to go to the labor room too early.
It was precisely that. (At least for the movie's second half. The first is rough.)
Stop Making Sense at a packed theater in college. I was the quintessential 80’s guy (white man’s overbite) but we were dancing in the aisles the whole time. Movie ended, we bought another ticket and immediately watched again. Must have seen it 6-7 times in the theater w/ different groups each time.