The kind of movie that shows no other rules apply other than good storytelling. I didn't know it was based on a play and I hadn't read the log line, so when I sat down to watch it, I figured it must be about a couple of folks hitting the road, singing, making records, dancing, etc. That's not what it's about...
It's all about the band, the producer, the manager, and the whole situation. It's not a movie that will tell you you need to have a protagonist. Instead it focuses on people, some of them good, some of them bad, all of them with their own histories, their burdens, their joys, follies, and their pains.
I can see how the play won a Pulitzer and it was wonderfully translated to the screen. The screenwriter craftily broke with expectations during the beginning of the story, but that doesn't mean it isn't a driving force as a theme. You just don't know when you're gonna get it and when it's going to drive home.
If I knew any of 'm, the only thing I would be able to tell them is, "Great job."