Right now I'm "reading" (actually listening to) The Wizard of Oz, read by Anne Hathaway on audiobook. I love Hathaway and am enjoying the story, but it's pretty clear she was influenced by the movie. To be fair, the book and the movie are pretty similar so far; but even the way Hathaway does the voices seems to imitate the way the characters were portrayed in the film.
This isn't a bad thing, but it's interesting to me how certain versions of a story become the one everyone's familiar with, and later interpretations kind of have to be in conversation with that version in order to be relevant. For example, The Phantom of the Opera is one of my favorite books of all time, and in my mind the book and the musical are two separate entities. But when I first think of Phantom, admittedly my thoughts turn to the Andrew Lloyd-Weber musical. That was the prism through which I approached the novel. So it was super-interesting for me to watch a silent movie version of The Phantom of the Opera starring Lon Chaney--which, unlike every other version of The Phantom I'd seen, was clearly in conversation with the book, NOT the musical. I'm not saying it was the best version, just that it had a very different sensibility from the contemporary adaptations I'd seen.
What about books like Dracula, or Sherlock Holmes, two of the most adapted novels/characters in literature AND cinema, not to mention plays? When I was reading Dracula, I personally couldn't help but think of the 1992 movie Bram Stoker's Dracula, and picturing Jonathan Harker as Keanu Reeves, Mina as Winona Ryder, etc. That movie is actually pretty faithful to the book (probably why I couldn't help but associate the two), but I don't think it's the definitive version, just the one I'm most familiar with. I'm not sure there's an adaptation that has become the "definitive version" of Sherlock Holmes, either, although I enjoy the hell out of nearly all the Sherlockiana I come across. No matter how good it is, it still feels either derivative of or in conversation with the original stories.
In both of these cases, the original versions are still what sets the standard for the characters and the story. But why is that? Why have Oz and Phantom been superseded by a movie and a musical, respectively, while Sherlock and Dracula still rely so heavily on the original text? Is it the quality of the books? I don't think so; as I said, Phantom is one of my favorite novels, and Dracula... well, it has its moments, but it's not the best thing I've ever read. I also don't think the quality of the adaptions have anything to do with it, since there are some truly kick-ass Sherlock adaptations.
Maybe it has more to do with the fan base. Sherlock Holmes fans still go to 221B Baker Street and read the original stories, while Phantom fans (Phantomites?) identify more strongly with the musical.
Have you ever come across an adaptation that overshadowed the original work? What do you think makes something a "definitive version"?