Compiling a list of the 50 Greatest Villains in Literature, without too much recourse to comics and children's books, proved trickier than we'd imagined - but gosh it was fun. It's perhaps the nature of grown-up literature that it doesn't all that often have villains, in the sense of coal-black embodiments of the principle of evil. And even when it does, it's not always so easy to tell who they are. Is God the baddie, or Satan? Ahab, or the white whale?