It's happened to all of us. We read a novel that blows us away, and a few years later its title appears on posters underneath the face of Harrison Ford or Natalie Portman. But at some inevitable point in that darkened theater, the movie takes a turn we didn't expect. Our eyebrows go up, our lips turn down, and the disappointment begins. Maybe the wrong director or writer can curse an otherwise excellent project — or maybe some things were just never meant to be filmed. Here are 10 books that io9.com thinks should never have been committed to celluloid.