There are a variety of different ways to tell a time travel story. You can be like Dr. Who and go the fun and loopy route where the science isn’t really discussed and the focus is on the characters and the adventure. While fun, the danger here is that the fare might come off as very light or, perhaps, too fantastical, depending on your tastes.
You can also be like 12 Monkeys and follow a series of twisting plot arcs across different timelines to tell a very dense and compelling sci-fi thriller tale. The danger here is that you botch the continuity and end up creating holes in your plot. While this hasn’t been the case with 12 Monkeys, many time travel stories fall into the trap of contradicting themselves with too much complexity, or too many time lines, or too many time loops.
I think NBC’s new show Timeless is a nice middle ground between these two options. It provides a succinct set of time travel rules that allow for the show to generate fun episodes and avoid massive plot holes caused by too much jumping through time.
The two stated rules are:
1.) If you change something in the past, it will affect the present in unknown ways.
2.) You cannot go to a place you’ve already been to. This can effectively be dubbed the “no do-over” rule.
The first rule allows for the writers to put together some fun and interesting plot devices, changing our present in small ways or allowing time changes to shape the characters in different ways.
The second rule, and I think the more ingenious of the two, succinctly explains away why the heroes (or even the villains) can’t just go back in time and retry their plans until they get them right. This immediately solves a lot of questions for the viewer and explains why the team has to jump through time to a different period every episode. It also altogether avoids any confusion that might be caused by overly complex overlapping timelines or events.
Compare this to DC’s Legends of Tomorrow, a show very similar to Timeless in feel, but of course featuring superheroes as the protagonists. The show never actually explains its rules for time travel, which has led to some eyebrow raising moments. For example, when Sarah Lance’s sister dies, the team’s captain, Rip Hunter, can’t really provide any meaningful reason why Sarah can’t go back in time and save her. It became clear at this point that the writers wanted to remove Laurel Lance from Legends’ sister show Arrow, but without good working time travel rules, the explanation was paper thin and felt totally unbelievable.
As to why the Legends never repeat missions, the closest explanation given is that in a “time travelers duel” the travelers will just keep looping attempting to change each others’ actions. Sarah gives this as an excuse as to why they can’t save another fallen friend, but it isn’t a very fulfilling explanation. I think if the show had more concrete rules, it would be more fun to watch, and it wouldn’t leave me asking why things do or don’t happen.
If you’re ever planning to write a time travel story, I would hold up Timeless as a good example to follow, largely because its rules for the technology are so simple and elegant. Of course, you don’t have to use their exact rules, but I think you need to have some thoughts about how your system works, and it should be consistent. With something as difficult to plot as time travel, I think simple will often be better.
And even if you aren’t planning on writing a time travel story, I still think you should check out Timeless. It’s a fun show and well worth a watch!