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The film derived from the first third of the original script. M. Night Shyamalan felt no connection to the last two thirds of the text, and decided to discard them.
Writer/director M. Night Shyamalan always had Bruce Willis and Samuel L. Jackson in mind to play the roles of David Dunn and Elijah Price.
The film is shot as a series of long (very long, by Hollywood standards) tracking shots, often with stark shadows or unusual camera angles, to mimic the storyboard flow of a comic book.
M. Night Shyamalan: [car accident] A car accident is a pivotal point in David and Audrey's relationship.