What is your opinion on unresolved/unexplained plots?

Do you like movies and books with plots that are open to interpretation? Movies and books that end unresolved with many possible explanations and answers?

I just watched the movie Mulholland Drive and I have to say, it’s one of the greatest movies I’ve ever seen. It’s so great that I will be watching it again tonight with several of my roommates.

But I know that some people don’t like movies that seem full of non-sequiturs and bizarre plot elements that add to the mysteriousness of it. While I don’t find Mulholland Drive to be confusing and I do feel I understand it, I also understand that David Lynch certainly intended for viewers to interpret the movie in a variety of ways.

I do not mind this as long as the writer has some idea of what they are doing. “Making it up as they go along” is a grave offense…there should be some idea of a “big picture” even if the viewers/readers are never fully exposed to it.