Well, it's called Before Midnight, so that might be part of the confusion... although your joke pretty much still works!
I can't say this strongly enough: watch all three films. It's watchable on its own and can be appreciated, probably, but you would be missing out on the whole point -- the films are intended to work together and in relation to each other. Additionally, the first two are also just supremely good, and not very long, and readily available. Get a hold of Before Sunrise and watch it. If you don't like it you're not going to like the other ones. If you do, well, then I envy the experience you're about to have. Watch 'em all.