I ran into "The Enchanted" 1984 - confused by the plot as a "related question" and I find myself intrigued by a secondary mystery. User HTG (not around since some time last year) mentions in the comments that they "have the book".
Never saw the movie, but I have the book somewhere in my basement. Loved it when I was younger! – HTG Nov 25 '14 at 3:09
However, I've found no indication of the film being based on a book on the IMDb page. I've done some ISFDb searches for books named The Enchanted, or starting with that title, and written at or before 1984, but have had no luck.