"One way to improve a screenplay is to find a way to look at it from another viewpoint – whether the story is to be optimistic or pessimistic. If we take the notion of optimism versus pessimism and look to Aristotle, we can come up with a truly original ending for our scripts. Aristotle defined a "reversal" as being a plot change by which the action veers round to its opposite. According to Aristotle, the best reversals are caused by the main character’s recognition of something that causes the reversal, so it doesn’t come out of left field, that is, it must be subject to the boundaries of probability or necessity. The reversal arises out of the recognition of something that could have been seen before, but was not. This is where we reach those edges of boundaries that will help you find that original twist you were looking for.
One of the cornerstones of my method is the use of the main character’s personality to drive the plot. An example of recognition and reversal occurs in The Line Of Fire. This is Frank Horgan’s (Clint Eastwood) recognition that the field office number is an anagram, and that unraveling a different anagram can reveal the secret of the would-be assassin’s identity. We have been directed towards a pessimistic ending – that is, it’s been set up in Act I that Frank won’t catch Leary (John Malkovich) in time, and Act 2 has furthered this expectation, but this recognition of the anagram is what allows for the reversal to create the opposite outcome in the third act. Frank has gone from being pessimistic to being optimistic.
Another example of recognition and reversal occurs in The Usual Suspects, in this case, the reversal is of the audience’s expectations. It is the audience’s optimistic belief that "Verbal" (Kevin Spacey) is innocent that allows us to enjoy the reversal when he’s revealed by his limp to be the perpetrator, and not the victim. We have gone from being optimistic to being pessimistic."
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