Doctor Who
This show is fantastic, and is an example of a good use of time travel to tell a story. I'm referring mostly to the reboot of Dr Who, and most specifically the seasons with the 9th, 10th, and 11th Doctors. I'm not familiar enough with the originals (though the 4th Doctor is still stuck in my memory), and after the 11th Doctor, it lost its appeal for me a bit and I stopped watching.So, obviously the show is built around time travel. Doctor Who is a Time Lord, and his ship is a Time Machine. In that setting, Time Travel is fundamental and it is used to tell stories in pretty much any time or location. And it works. They don't try to explain how it could work in physics, and they don't need to. It's like the Force in Star Wars. It's not trying to suggest that this is how it works in reality... just that setting.
Most important though, Doctor Who as a show doesn't use time travel to get around problems in a cheesy way. It doesn't write itself into a corner and then fall back on the catch-all solution of time travel to fix a problem in their writing. And that's the mistake I see in things like...
Avengers: Infinity War & Endgame
I'll start on this example by saying I really like the Marvel Cinematic Universe (MCU). My favorite on the list is the first Avengers movie: "Marvel's The Avengers". I've seen all but "Spider-Man: Far From Home" at the time of writing this. So, while I'm about to complain about Infinity War and Endgame, I like the movies.Infinity War set up the problem, which was that Thanos succeeded. He gathered all the stones, and ended half of all life. And that's pretty much where the movie ended. I was actually really excited because it was the Empire Strikes Back of the MCU. The bad guys won, and the good guys are scrambling to pick up the pieces. And I was especially excited to see how the good guys would come back and solve the enormous problem. So, Endgame was a big exciting thing for me when it came out. And it definitely delivered from the perspective of emotional engagement.
But, Endgame used time travel as the solution to the problem. And I realized at that moment that letting Thanos snap his fingers and erase half of life in Infinity Was was the mistake. They wrote themselves into a corner, and time travel was the only solution. I know that the comics allow time travel. I dislike it just as much there. The X-Men movies are all messed up because of it too. Anyway... with the setup of Infinity War, there was literally nothing Endgame could do that would be satisfying. Thanos wielding infinite power and winning is the worst corner to paint yourself into.
If the writers did it on purpose, and expected to use time travel in Endgame, then I'm not impressed. If the writers just couldn't come up with something better, then I'm disappointed. I think they would have been better served if Infinity War was the story of Thanos collecting the first 5 stones, and Endgame should have been the defense of the 6th stone. Infinity War still gets to be about the bad guys winning... Thanos got 5 of the stones and is really powerful. The 6th stone gets defended in Endgame with every possible trick and hero while they try to figure out how to get the other 5 stones back away from Thanos. At the end, Thanos asks why they fought so hard to stop him since he was just trying to help. He's genuinely confused. Right up until they kill him to stop him from trying again.
Another example of a good use of time travel is...
Star Trek Movies Reboot
When they decided to reboot the Star Trek movies, I think they actually did a good job. The movie was really engaging and fun, and used a lot of the campy science-babble that doesn't make sense that is normal for Star Trek. But the story is that a really pissed off Romulan comes back in time and changes something fundamental to the Star Trek universe right as the Kirk-Era story is beginning. And I think they mention something about a branching of reality, so they can say that the older Trek still exists, but so does this new Trek. And that's it for the time travel. It's used as a way to explain the reboot as being part of the existing setting in a very neat way. It's actually really impressive. It's not used to solve a problem of the writing that they did already... It's used to support the setup of the story, and I approve of it. But here's another example of bad use of time travel...The Terminator Series of Movies
The Terminator movies have time travel as fundamental to the setting, like Doctor Who... but... the story is also based on the idea of cause and effect. The concept of cause and effect is essential to the story because humans from the future try to come back in time to change things, so the robots don't ruin the world and wipe out most of humanity. But this jumps right into paradox head first.Time travel paradox is the idea of going back in time to change something, and if you succeed, the motivating event that caused you to go back in time isn't there anymore, so the second time around, you have no reason to go back in time to do that. So, if the humans succeed in stopping the robots by going back in time, when that point in time occurs again, no one will be there with any reason to go back again. They won't know to go back in time and change anything. So, it's a paradox. Can't happen.
While the Star Trek reboot used time travel to change something in the past, it did so to explain the reboot and offered the idea of a branch in reality. The Terminator movies base their entire idea on going back to change the past and seem to ignore paradox entirely.
