"Really good fiction and really good cinema attain excellence by not being obvious. A simple way of looking at it is that you generally don't know what's going to happen in the end. A movie like Slumdog Millionaire failed for me because there was nothing to interpret, nothing to think about. It was a visually exciting movie but it asked nothing of the audience. I want to be challenged. From that standpoint No Country For Old Men (2007) was brilliant. Sorting out the whys and wherefores of the character, Anton Chigurh was a meaty task in and of itself.
There's an important point: both fiction and film rely on characters and if they are one-dimensional then your story will be too. It's far too easy to make inflexible characters whose actions are quite predictable. Worse still you can create characters who commit acts that are inconsistent with their personalities. Jake LaMotta in Raging Bull (1980) always acts in accordance with who he is. But who is he? Why is he so true to his nature to the point that he alienates his wife and brother? Does he have no limits?"
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