There have been some great novelists, such as F. Scott Fitzgerald, who attempted screenwriting and failed because they didn’t understand the necessity of extensive changes. In today’s world, a popular novel written by someone like Michael Connelly or Robert B. Parker, is considered a success if it sells in the range of 300,000 hardback copies and about 1,000,000 paperbacks. That sounds like a lot of books but when one considers that the United States has 240,000,000 people, it doesn’t seem that gigantic. So, for one of these novels to be translated to the silver screen, it has to be made to appeal to a lot more than the readers of the works to be a successful movie, hence, the intervention of the screenwriter.
Robert B. Parker is not interested in screenwriting although he has dabbled in it. He likes the philosophy of Raymond Chandler: "When you do a screenplay, it belongs to them (the studio), when you write a novel, it’s yours."
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