Time Travel in Movies

Time travel movies are some of my favorite kinds of movies. They make for an interesting story and there are so many different ways to use the concept. As time travel is a very vague concept, movies have addressed it in different ways and established different rules and logic for how time travel works. The hardest thing about time travel is that if you aren't careful, the events and logic will begin to contradict themselves and cause the audience to question how certain events happened. After watching many different time travel movies, I have grouped them into 7 different types based on the logic they utilize. I wanted to share each type of time travel movie, how the logic works as well as which ones have the logic that holds up the best.

Spoiler Warning for time travel movies as I will be talking about plot points from many different films.

1. Change the Past

These are the most common types of time travel movies out there. The "change the past" movies involve a character or group of characters going back in to either (accidentally or purposely) change the current future or prevent someone else from changing it. The events in the past then have a direct impact on how things in the future turn out. An example of an accidental change is Back to the Future. Marty goes back and time and accidentally stops his parents from meeting thus jeopardizing his and his sibling's existence. While he remedies his mistake, his presence still impacts the future and thus changes are made when he returns. For movies with characters that purposely want to change things, we have X-Men: Days of Future Past where Professor X sends Wolverine back into to prevent the creation of mutant killing robots. A couple other examples are Deadpool 2, where Cable goes back to kill a child that kills his family in the future, The Adam Project where Adam (Ryan Reynolds) goes back in time to stop a company that creates a dystopian future and Looper, where Joe (Bruce Willis) goes back in time to kill a man that starts the mob. Both of these movies also involve the time traveler interacting with a past version of themself. Then you have the movies where time travel goes back to stop someone else from changing the past. This is in films such as Men in Black 3, J goes back to stop Boris from killing K, The Terminator Franchise, John Conner sends people back to stop a Terminator from killing either him or his mom, and Star Trek: First Contact, the crew of the enterprise goes back to stop the Borg from preventing Earth's first contact with aliens. The biggest issue with the logic in these movies is that it introduces too many contradictions. If someone goes back and changes the past, then there was no reason for them to ever go back in the first place and thus the past wouldn't have ever changed. Things like that get way too complicated. These movies are fun but it's best not to think about the logic too much.

2 Movie is a circle

The movie is a circle of time travel logic is another fairly common type of time travel logic. This type of movie uses the logic where someone goes back in time to change something, only to have it be revealed that their past self went back in time which ensures their current events and is essentially a part of the timeline. The time travel essentially experiences a loop before moving forward in their timeline. Harry Potter and the Prisoner of Azkaban is the best example of this. Harry is saved from the dementors by a mysterious figure that, when Harry goes back in time, turns out to be the time-traveling Harry saving himself. Interstellar is another good example of this. When Coop is sucked into the black hole, it is revealed that he is the one that causes his past self to find NASA and head into space in the first place. Bill and Ted's Excellent Adventure use the same logic where Bill and Ted leave useful items for their past self to make sure they can escape the police as well as Tenet where it is revealed that the Protagonist recruited Robert Pattenson's character who ultimately helps the protagonist become who is. Finally, in Arrival Louise uses her future memories to help with events in the present day. The logic in these types of movies holds up a little bit better but it is still really hard to wrap my head around.

3. Time Loop Movies

Time loop movies are a lot simpler to understand than the previous concepts. The basic idea of these movies is that the main character is trapped in a time loop living the same day over and over. What the person does has no impact on the future, nor can any else remember what happened. The biggest example of this is Groundhog Day where Bill Murray's character gets trapped in a time loop on Groundhog Day until he performs the perfect sequence of actions to allow him to exit the loop. The reason for the time loop is never explained nor is it explained how he gets out of it. There have been other movies that have taken the same idea but Groundhog Day was the first. Another great example is Edge of Tomorrow where Tom Cruise has his day reset every time dies until he defeats the attacking aliens. There is also Happy Death Day which is essentially Groundhog Day as a slasher film, Tree has to keep reliving the same day over and over again until she finds the person that keeps killing her, and finally, Palm Springs where Sarah and Nyles have to keep reliving the same wedding until they figure out how to stop the loop. All of these have the same basic premise and don't put much thought into the actual mechanics of the time loop other than it being an obstacle.

4. Time Travel Antics

This group of movies utilizes time travel as more of a setting than a part of the plot. Even though people travel to the past or future, they are more just there to interact and don't do anything that changes things. One example of this is Last Night in Soho. Eloise finds herself inside the body of a girl from the 1960s whenever she goes to sleep. She doesn't do anything to change the past and just kind of witnesses events as they happen. Star Trek IV: The Voyage Home is another example. The crew of the Enterprise travels back to the 1980s. They aren't there to change anything, they just need to pick up a couple of whales to help them in their present. We also have 13 going on 30 where Jenna Rink finds herself 17 years into the future. She doesn't need to accomplish anything, she is just there to experience life. There is also A Christmas Carol, where Scrooge goes to both the past and future, and sees events play out but can't interact with anything in those times. Finally, we have the TV show Doctor Who where the Doctor and his companion travel throughout time interacting during various events without having any impact on the future. This type of time travel story is more carefree as nothing the characters do has any impact on the future.

5. Alternate Realities

The alternate realities time travel approach or the multiverse is the idea with time travel that makes the most sense to me. Essentially what you have is every time someone makes a change in the past, instead of directly changing the future, it just creates an alternate timeline that runs in parallel with the current timeline. This concept eliminates the contradiction and confusion that some of the other time travel approaches have on this list as changing the past doesn't directly save the past. Avengers: Endgame is the best example of this with Bruce Banner explaining "If you go into the past, that past becomes your future, and your former present becomes the past, which can't now be changed by your new future!" The 2009 Star Trek is another good example, Nero and Spock get sent back into and inadvertently change the past. Instead of changing the future and themselves, it just creates a timeline with both old Spock and new Spock existing. Nothing new Spock does impacts old Spock. Some other examples are The Flash where Barry saves his mom's life and unexpectedly hops realities, It's a Wonderful Life and Shrek Forever After where George Bailey and Shrek experience alternate realities where they were never born, and Rick and Morty where the duo explores various realities that had one event change and creates a new timeline. This concept makes the most sense to me and allows for the most streamlined stories.

6. Save the Future

This grouping is kind of in the same vein as the "change the past" movies where choices characters make do impact the future. However, these movies have a distinct difference of having people being pulled to the future instead of the past. In these movies, someone from the future runs into trouble and has to bring someone from the present up to help them. Usually, these missions don't end in success and the person from the present has to go back to their time to change things and prevent the future. The Tomorrow War is a good example of this. In the future, Earth is under attack by an alien force so the future government pulls people from the present to fight in their war. When that fails, people in the present try to stop the aliens in their time from becoming an issue in the future. Another example is Meet the Robinsons. Wilbur comes to the present and recruits Lewis to help him fix a time machine. A final example is Back to the Future Part 2 where Doc brings Marty to the future to help with Marty's kids. Both of these films also end with the main character making changes in their time to make for a different future. This logic has the same issues as the "change the past" movies but they are still fun to watch.

7. Accelerated Time

This grouping is probably the loosest example of time travel. In these movies, time can still only be moved in one direction with nobody traveling in the past. However, these movies have characters or groups of characters that travel through some sort of abnormality that causes time to move slower for them than everywhere else. They can't just travel to any time but they do experience time much faster than everywhere else without feeling the effects. Interstellar has a good example of this, when Cooper and his crew land on a planet closer to a black hole, time movies significantly faster for them than everyone else. Every hour on this planet ends up being 7-8 years back on Earth so when they return back to their ship, a few hours passed for them but 30 years passed for everyone else. Another example is in Lightyear, every time Buzz tests his hyperdrive, 4 years pass down on his planet while no time passes for him. So after numerous tests, about 80 years pass on his planet while very limited time passes for him. Technically these aren't time travel movies as much as time acceleration movies but it still adds something different to the time travel concept.

As seen here, there are many different approaches to time travel in film and television and it is fun to see so many different movies embracing the concept. For another breakdown of the different time travel concepts check out this video.

https://www.youtube.com/watch?v=d3zTfXvYZ9s