Conversation so far:
When did the development of the film Chapter 27 start?
The script took Schaefer four years to write, but when it was finished, the film came together quickly.
What was the inspiration for the movie Chapter 27?
Chapter 27 is a 2007 biographical drama film depicting the murder of John Lennon by Mark David Chapman.
Why was the movie titled Chapter 27?
The title Chapter 27 suggests a continuation of J. D. Salinger's novel The Catcher in the Rye, which has twenty-six chapters.

Question: Why is the novel The Catcher in the Rye important for this movie?
Self-contained rewrite: Why is the novel The Catcher in the Rye important for this movie?