When you make a movie, always try to discover what the theme of the movie is in one or two words. Every time I made a film, I always knew what I thought the theme was, the core, in one word. In “The Godfather,” it was succession. In “The Conversation,” it was privacy. In “Apocalypse,” it was morality.The reason it’s important to have this is because most of the time what a director really does is make decisions. All day long: Do you want it to be long hair or short hair? Do you want a dress or pants? Do you want a beard or no beard? There are many times when you don’t know the answer. Knowing what the theme is always helps you.

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I remember in “The Conversation,” they brought all these coats to me, and they said: Do you want him to look like a detective, Humphrey Bogart? Do you want him to look like a blah blah blah. I didn’t know, and said the theme is ‘privacy’ and chose the plastic coat you could see through. So knowing the theme helps you make a decision when you’re not sure which way to go.