The Time Traveller's Dilemma: Time Travel, Part II

I tend to be a bit wary of time travel stories (Dr Who notwithstanding-- one show which handles the points below well). The main point of my discomfort is that the issue of whether or not one can change the past, and the logistics of that answer, can open up a whole can of very squirmy worms. If inadequately addressed, you can end up knee deep in plot holes, unfortunate implications, or both. As with any feature of your fictional universe, a big part of dealing with this issue is to decide what the story rules are as far as changing the past, and then, once those rules are established, sticking to them.

There's also a deeper implication for your story's meaning, however. This is most prominent when the story touches on or centres around major historical events (assuming you've dealt with the time traveller's paradox... quantum theories about the multiverse should help). If your characters can and do change events, the new outcome and how the narrative treats this change-- as positive or negative-- will carry much of the story's values. Similarly, if the characters can theoretically change history and fail to do so you can land straight in the unfortunate implication zone, particularly if these events are man-made tragedies, as we'll discuss more on Friday. The only way I've seen this handled well is when the characters face a choice between 'bad' and 'catastrophic' outcomes, and have to make a terrible choice to let one horror unfold to spare the world something even worse.

If you want to write about characters struggling and failing to change the past, I think the best route is to have a universe where the past is permanent (ie, the time traveller's paradox is in full effect). Much like stories of self-fulfilling prophecies, seeing the characters attempt to alter the past for the better and inadvertently become a critical part of shaping history as we know can be a painful meditation on acceptance if you let the story develop depth.