Spoiler alert: this structure breakdown contains information about the plot.
District 9 is a perfect example of the primary story strategy on which the worldwide entertainment business is based: use a popular genre as a vehicle to carry a larger theme.
A genre is a story model, but to understand the supreme power of genre in international cinema you have to break down both of those words.
“Model” involves the meaning package, like love, action, detective and science fiction. Why are there different story models? Because each expresses a different theme, each gives the audience a different strategy for how to live a good life.
“Story” means narrative drive, by far the single biggest element in a movie’s popularity worldwide. District 9 is more proof that movie stars don’t cause blockbusters, narrative does. For years I’ve been crying in the wilderness that the movie star strategy is the second biggest fallacy in movie history, right after the French auteur theory that says that the director, not the writer, is the author of the film.
Read the rest of John Truby's fascinating article: District 9 Breakdown