Books, Screen Plays, Movies--Amazing Transformations

Books are fascinating.  When they are transformed into movies it is amazing what has to be done to condense the book and turn it into more direct action and dialog.  The Harry Potter series of books by J.K. Rowling are full-length books.  The movies are abridged versions of the books that still carry the basic themes and plots.  I recently re-read Dan Brown's DaVinci Code and Angels and Demons, then saw the movies and saw the amazing transformations required to create the screenplay and the film version.  Today I finished listening to The Thin Man by Dashiell Hammett.  I am looking at the 1934 film and am again struck by the transformations.  The book has 31 chapters and the film runs for 75 minutes.  That film set the stage for many sequels for which the screenplays were written directly, using the characters developed by Dashiell Hammett.

Turning a book into a screenplay would be a great exercise in creative writing for language students.