I went to an advance screening of the mock-musical biopic “Walk Hard: The Dewey Cox Story” last night, which was far better than I expected it to be. It was unnecessarily heavy on the dick-n-fart jokes (including some full-frontal male nudity, which got the most sustained laughter of the night), but it survived on its clever and smart parody of all things musical.

The low point of the night came from two pimply, college-age chuckleheads who sat next to me, and spent the whole evening alternatively complaining about the movie or laughing hysterically at their own jokes. As they blabbered their way through the film, it became clear that, despite “Walk Hard” being an in-your-face parody, they didn’t really understand what was going on. Whenever the film would take an intentionally corny, cliche, biopic-style twist, the guys would groan about how predictable it was. And during a scene set a few decades ago, when they spotted some modern-day cars driving around in the background, one huffed, ”Those cars aren’t even old!”

Revenge was childish: One of them forgot their sweater on the floor, which I discovered when I accidentially stepped on it. I left it there.