One of the greatest sci-fi conventions is being "unstuck in time". Although there are MANY great instances of this condition, one of the most famous and most influential is (undoubtedly) Vonnegut's Billy Pilgrim. If you've never read (or seen, I suppose) " Slaughterhouse Five ", do yourself a favor and check it out! "Unstuck in time" is a classical way of questioning reality, sanity, free will, fate, mortality, and perception. Someone who finds themselves "unstuck in time" finds themselves fighting against accusations of insanity while struggling to unravel a mystery that inevitably holds the key to their fate. One false move and they could become trapped in a time that they don't belong in, they could irretrievably alter the path of the future, they could destroy the lives of those around them, they could conceivably live forever... ANYTHING possible can happen. So the question becomes - what have they done before?