I read and write mysteries and in those you often haven't a clue who the 'big bad' is, or even if there is one. Often anyone and everyone's a suspect; the nicest guy could turn out to be a killer; the one with the worst personality might save your life. And even in books that aren't traditional mysteries, the ones with a 'puzzle' or question or mysterious element to them often do not have a clear cut antagonist either. How can you when you haven't a flippin' idea who the 'bad guy' is?
(Okay you might have an idea who or she is, but then again, you might be wrong.
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