(OK, there's one more thing I just have to say. It's about the ending. I suppose it could be construed as a SPOILER, but I'm giving no details.
The movie doesn't work if the ending goes the other way. I know there are people who believe otherwise, but I will defend this until my last breath. It would make perfect sense for the film to end with the opposite ending, but that ending wouldn't make the film have any kind of relevance. I'm not just talking about relevance from a shock standpoint, I'm saying there would be no relevant reason for the film to exist. There are those who say the on-screen ending is an "easy way out", but in my book the movie becomes about 97% less daring if it switches the ending. The ending, as is, gives the movie its flavor.)