I was reading yesterday the book Why Sinatra matters, by Pete Hamill when I came across this quote-

The birth of a creature of human fantasy, a birth which is a step across the threshold between nothing and eternity, can also happen suddenly, occasioned by some necessity.

An imagined drama needs a character who does or says a certain necessary thing; accordingly this character is born and is precisely what he had to be.

Luigi Pirandello, who wrote that 52 years before the release of Star Wars [a necessary movie with a necessary hero], but many years after great works with necessary characters.