Like a lot of people over recent days I've been indulging in Back To The Future nostalgia. Rewatching everyone's favourite time travel comedy led me to think about the mechanics of its time travel rules, and those of other classic sci-fi films that rely on time travel for their plots.
Here are five classic sci-fi films ruined by their own time travel blunders:
Back To The Future & Back To The Future Part II
We all had great fun on October 21st with "Back To The Future Day" (I even wrote a post about fun Back To The Future Part II trivia). But the thing that's often overlooked is that for all the Doc's big science-y talk, the time travel in the film doesn't make any sense.
The reason is simple enough: when a change is made in the past, it creates an alternate timeline. We know this, because Doc Brown tell us in Part II, when he and Marty return to an alternate Hill Valley in 1985. In this reality, Marty's Mom is married to Biff, his father is dead, and Doc Brown is committed.
"The time continuum has been disrupted, creating this new temporal event sequence resulting in this alternate reality."
This comes about because 2015 Biff finds the Sports Almanac, and travels back to 1955 to give it to his younger self, resulting in an alternate future/present where all of the above has taken place.
However, Biff isn't the only one to use time travel to create an alternate future. At the end of the first film, Marty returns to a wholly different 1985. In this version of 1985, thanks to Marty's machinations in 1955, his parents are everything they weren't before he got in that time machine: loved-up, rich and successful.
George is now a famous science fiction writer, they live in a nice big house, they even bought teenage Marty an expensive new truck. You may be thinking: so what? Marty used time travel to his advantage. Good for him!
Here's the thing though: Marty shouldn't exist in this version of 1985. At least, not this Marty, not the Marty that got in the DeLorean with Doc and went to 1955. The events in '55 created an alternate timeline - a timeline where Marty accidentally invents rock n' roll, George is an assertive, successful man and Biff is his car washing lackey. This reality contains an alternate George, an alternate Lorraine and an alternate Biff. So there should be an alternate Marty.
Marty McFly shouldn't be able to waltz out of his time machine into this reality, because a version of him should already exist.
Oh and as an aside, even if somehow he was able to just drop into a Marty-shaped hole in this reality, isn't it weird that his parents don't seem to notice - or just plain ignore - his striking resemblance to someone they both knew in high school? Someone who was basically responsible for their getting together in the first place? Someone who pretty much invented rock n roll? Or do they just think they went to school with a guy who ended up designing jeans and underwear?
The Terminator & The Terminator 2: Judgement Day
The first two films in the Terminator franchise are undoubtedly modern sci-fi classics, but they also play pretty fast and loose with the rules of time travel (and even with the rules established in the films themselves).
The films are built on a paradox. The plot is that in the future there is a war between the killing machines of Skynet, a human-made self-aware artificial intelligence, and the plucky human resistance, led by John Connor. In this future, John Connor learns of Skynet's plan to send one of their Terminator machines back in time to assassinate John's mother Sarah before he was even born. In return, John sends back his lieutenant Kyle Reese back to the same point in time to protect Sarah.
It's in the then-present day of the original Terminator film that things get a bit paradox-y. In between bouts of running away from the Terminator, Kyle Reese and Sarah Connor find the time to sleep together and conceive John Connor, the man who will in the future send Reese back to protect his mother and ensure that he is born so that he can in the future send Reese back...you get the idea.
The time paradoxes don't even end there, because after the Terminator is destroyed the microchip in its skull survives, and finds its way to a technology company called Cyberdyne Systems. In case you haven't guessed, that company go on to create Skynet.
All this leads me to the theory that Skynet's plan had to fail to ensure its own existence. Think about it - if Arnie's unstoppable killbot had succeeded, instead of being destroyed by a waitress, then there would be no John Connor to lead the human resistance but also there would be no chain of events that leads the destroyed Terminator's microchip to be picked up by Cyberdine Systems and Skynet to be created. Therefore if Skynet's plan would have been a success then Skynet itself would never be invented. Clear?
Looper is one of those films that seems brilliant when you first come out of the cinema but whose internal logic gradually disintegrates the more you think about it.
The film is set in the future, when time travel is use for assassinations. Mobsters of the future (a future further ahead than Looper's present) send back those they want killed. The assassins - "loopers" - kill them, take their payment in gold bars and dispose of the bodies. The future police aren't going to find bodies that were incinerated decades earlier.
Once a looper's contract ends, their own future self is sent back for them to kill, known as "closing the loop". Our protagonist, Joe, fails to kill his older self. Old Joe is scouring the past for a child who will in the future become a crime lord with telekinetic powers called The Rainmaker who is responsible for the death of Old Joe's wife.
In the film's final showdown in a cornfield, Old Joe is out to kill Cid, the child who will become the Rainmaker. He is protected by his mother Sara. With Old Joe about the shoot Sara, Joe realises that this event will be the catalyst that will set the child on the path to becoming the Rainmaker. Joe makes the decision to shoot himself, and his death immediately erases Old Joe, saving Cid and Sara.
The problem with this ending is that it basically negates everything that happened in the film. If Joe dies at that time then he never grows into Old Joe. If he never grows old, he never meets his wife, his wife isn't killed by the Rainmaker's men, and he never gets sent back to the past. If he's never sent back then he doesn't try to kill the Rainmaker, and if he doesn't do that then he's never in the cornfield where his younger self kills himself. So none of the film ever happens.
We can't even alternate timeline our way out of this paradox - we already know that events in the past directly alter those in the future. We see Joe carve a message into his arm which then appears as an aged scar on Old Joe's arm. We also know another looper named Seth is tortured for failing to close his loop, and we see his older self lose limbs and get disfigured as the torture goes on.
If we accept that the past and the future are directly linked, then Joe's selfless actions at the end negate everything that happened. Looper's story never happened.
Clearly the lawmakers in the Timecop universe have seen the first two Back To The Future films. In this world, time travel is policed to ensure that no one travels back in time for nefarious purposes or get-rich-quick schemes a la Biff.
That doesn't stop the magnificently evil Senator Aaron McCombe from hatching a plan to travel back to the past to get money to ensure his bid for the presidency is successful, and timecop Max Walker is out to stop him.
The film has two main rules that underpin its use of time travel. One is that it's not possible to travel to the future (because it hasn't happened yet) and the other is that two versions of the same matter cannot occupy the same space.
In the film's climactic fight, Van Damme's timecop Max Walker uses the latter rule to his advantage, pushing a younger version of McComb into his present version, making them explode in a bloody mess because science.
It should be fairly clear why the whole "two versions of the same thing can't occupy the same space" is hokum, but even if you accept that at face value, the two McCombs are a decade apart in age. Our cells are being replaced all the time, so while the two McCombs may be the same person, they are not the same "matter".
What should have happened when Walker flings one into the other is that they might, at best, knock each other over, while Walker looks on sheepishly.
Bill & Ted's Excellent Adventure
I'll just come out and say it: the time travel logic in Bill & Ted's Excellent Adventure makes absolutely no sense. I know, it's hard to believe from such a highbrow art-house film, but it's true.
Loveable idiots Bill S. Preston, esq. and Ted Theodore Logan are led down the path of time travel by a visitor from the future. Their guide Rufus travels back from seven hundred years in the future (the year 2688) to tell them that he lives in a utopian society inspired by the music of the duos' band Wyld Stallyns. Rufus informs the two doofuses that if they fail their upcoming history exam, Ted will be sent off to military school and Wyld Stallyns - and therefore the utopian future that somehow sprang from their music - would never exist.
Bill and Ted accompany Rufus in his time machine on a madcap jaunt through history, plucking figures like Socrates, Napoleon Bonaparte and Billy The Kid from their own times to the present to assist in their history report - with, er, "hilarious" results. In the end, though, the boys pass history, are inspired to form Wyld Stallyns and the Rufus' utopian society comes to pass.
Much of the time travel and interaction with historical figures is played for laughs, but the very premise of the film is faulty in much the same way as The Terminator's is.
Rufus goes back in time from 2688 to 1988 to ensure Bill and Ted pass their history exam, form the band and thus lead society on a path towards a future utopia. But if Rufus doesn't make the trip then the boys fail, Wyld Stallyns never amounts to anything and Rufus' society never exists. In order to make the trip he has to make the trip - if he doesn't travel into the past then the future from which he travels from is never created. Essentially, Rufus is creating his own past.
I hope you've recovered from all that...
Those are five films undone by their own time travel mistakes, confusion and paradoxes. What do you think? Do you have any theories that make these films work, or do you care if they don't work? What are other films with time travel anomalies?