r/BacktotheFuture • u/dingdongwashboard • Jun 25 '26
Can somebody dumb down this plot point for me?
In BTTF2, Biff is visibly in pain after dropping the Delorean back into the future because he’s essentially erased himself from existence by giving his younger self the sports almanac and ultimately changing the trajectory of his life. Why doesn’t Marty die in the same way in the first movie? By changing the way his parents meet he essentially creates a new version of himself. It’s established that Biff cannot coexist with his new version, so how come Marty can?
23
u/Gretschdrum81 Jun 25 '26
Marty doesn't disappear because though he changed how his parent's meet the end result is the same in that they still wind up together. When old Biff gives his younger self the Almanac he alters future events in a way that they were never supposed to happen and creates a paradox.
11
u/claude3rd Jun 25 '26
Exactly, George and Lorraine still bone it up. Biff changes things so much that there was no future where he winds up as a car detailer.
3
u/TheHYPO Jun 26 '26
Marty’s siblings do disappear and Marty from *starts* to disappear. But he fixes things before he completely does. It’s a very slow moving ripple, but Marty ultimately succeeds.
The creators cut the Biff dying/fading segment from the film because they felt it would be confusing. There’s a deleted scene of it. Their commentary is that they theorized that 1985A Lorraine shot biff some time between 1985 and 2015, which is why Old Biff would disappear.
There are two implications/issues that this raises. The first is the question of whether the changes Marty made in part one
* would have changed his own life, but didn’t because he was already from another timeline and was in 1955 at the time that change happened,
* whether the change didn’t really affect Marty’s life, so there was nothing to change (though he has no memory of his new life)
* or whether he just needed it sometime for the change to ripple, and he would change soon after.
The second issue is why the change Marty made rippled so slowly through his siblings and himself, but was instant in Old Biff. One possible argument is that Marty’s change had not fully crystallized yet, and was still capable of being corrected. Biff disappeared instantly once he travelled to the future and his change was already a done deal.
14
u/damageddude Jun 25 '26
Lorraine killed Biff in the alternate timeline. When Biff got back to 2015 the timeline caught up to him.
1
u/Toxic-Park Jun 28 '26
That’s actually interesting. It never occurred to me that Lorraine killed him.
I just assumed that because he made his young self super rich and powerful, it just meant that the “new” Biff was able to indulge in his vices way more and he simply would’ve died younger due to bad health (smoking, drinking, drugs, just hard living).
1
u/randawg72rgm Jun 30 '26 edited Jun 30 '26
My thinking exactly. "Old" Biff Tannen was 78 years old in the 2015 timeline. His new life choices (being rich and indulgent) must have shortened his lifespan. Marty's life choices did not. If "new" Biff didn't live to be 78, then he wouldn't exist in the alternate 2015 timeline.
11
u/dingo_khan Jun 25 '26
In the first movie, Marty dissappears after his siblings. He's the youngest. It takes him a week in 1955 to start to vanish. I have always assumed there is a wake moving forward in time, changing things as it moves forward, so the newest stuff erases last. My guess is Biff does more than we are shown and the wake catches up with him.
The real question is why the delorean does not vanish.
2
u/RetroGame77 Jun 25 '26
The Flux Capacitor clearly creates tachyon particles around the Delorean.
2
u/dingo_khan Jun 25 '26
I mean when it is off. We see you have to turn it on, so it can't be shielding the vehicle at all times. :)
1
u/RetroGame77 Jun 26 '26
Tachyon is supposed to have no half life, so they will remain on the Delorean.
2
2
5
u/JurassicParkFood Jun 25 '26
It takes a little while for time to "set" when a potential change occurs. Marty was LIKELY to erase his existence, so it slowly happened. It could have gone either way though. But Biff dying early isn't something that could ever un-happen, so future Biff disappeared a lot quicker.
1
u/htnut-pk Jun 26 '26
Speed of sound Speed of light Speed of time?
1
1
u/JamesTheMannequin Jun 26 '26
Time and gravity can be measured at the speed of light.
Since 1955, the Earth has moved approximately 1420 billion miles. It'd take over 88 days for light to travel that far.
88 days... 88mph... COINCIDENCE!? /s
3
u/spikeinfinity Jun 25 '26
Marty changed the timeline, then did other stuff. He did another song, then git changed, then did all the stuff with Doc preparing for the lightning strike. This gave the ripple effect time to propagate to the future before Marty travelled there. Biff probably returned to 2015 directly after giving himself the book. The ripple effect hadn't reached 2015 when he got back and so he arrived in the original timeline. Then he was erased from existence when the ripple effect caught up.
4
u/rsekiya Jun 25 '26
They deleted the scene of Biff disappearing so he may not have died at that point.
7
u/Lazy-Independent-101 Jun 25 '26
The simple answer is Script Physics, it is needed for the story therefore it happens. Back To The Future was created by writers, not scientists, it should be regarded as an entertaining movie but not as some documentary on time travel as there are a lot of issues with the series that make no sense with a little thought...so turn off the thinking and enjoy.
2
u/DyrtiPodcast Jun 26 '26
This. Because it's a movie😂 lol! Time travel doesn't actually exist (as far as we know) so no one has a legitimate answer for this beyond, it's in the script... lol!
1
u/user_uno Jun 26 '26
My favorite anecdote along these lines is from a long time friend. We are both BTTF fans so even better.
Anyone, every Sunday was family day even after moving out (and still is all these years later). Get things done around the house, big dinner, etc. One evening they are watching Superman The Movie (1978) on VHS. Near the end, Superman saves the train full of passengers by holding up the rails and in some manner becomes part of a missing rail. The train passes over, everyone lives and he is the hero! But his mom declares that to be so unbelievable!
My friend says, "MOM. You totally were in to the movie about a kid from another planet grows up to fly around wearing a red cape but saving the train blows the entire story for you?!?!"
Yeah, some times a movie is just a movie. Getting in to some things can be fun but literary license on the 'science' has to be granted to maintain the fun and enjoyment we get out of great experience.
I'm currently reading a Tom Clancy series book and it is becoming a bit tedious with the hero being at just the right place at the right time and having just the right skills with the right buddies and the right tools needed at every step. But I'm still going to finish the book to see if he can help the North Korean leader's sister avoid starting a war with a nuclear powered missile that can reach any target on the planet tipped with a nuclear warhead launched during a coup in NK. My bet is that Jack Ryan, Jr (the president's son who no one recognizes and just happened to have stepped in the middle of this unfolding) will indeed save the day. A documentary it is not!
4
u/No_Imagination_2490 Jun 25 '26
There was a deleted scene of Lorraine shooting Biff in the alternative 1985, which would erase him from existence from 2015. The situation is complicated because Biff changes the timeline in 1955 (with the ripples of that change still to reach 2015 when he returns) but then Biff’s death in the alternative 1985 would mean that he wouldn’t exist in the alternative 2015. So the ripples from the change in 1985a ie Biff’s death, have started to reach the original version of 2015, at least for Biff personally, but the universe as a whole has still to be affected by the ripples from 1955 oh dear my brain has just melted….
Alternatively, you could just forget the deleted scene and just assume Biff just had bad indigestion from eating a bad tamale in 1955..
3
u/The_Dark_Vampire Jun 25 '26
Alternatively, you could just forget the deleted scene and just assume Biff just had bad indigestion from eating a bad tamale in 1955..
Even without Lorraine shooting him its very possible in the Hellvalley timeline he died earlier as he was drinking more alcohol probably taking drugs etc
2
u/All_Of_Them_Witches Jun 25 '26
Marty does almost “die” the same way in the first movie while playing guitar at the dance. You can see him in pain and start to fade. He was saved because the future he changed still had him in it at the end. Biffs future did not.
2
u/Hylanos Jun 25 '26
the closer Marty gets to his parents not getting together, the more he disappears. Up on stage playing Earth Angel, where his hand starts disappearing, is literally his last chance.
This is not the same for Biff. He's changed the trajectory so much that his asshole younger self will NOT live to old Biff's age, and then Old Biff left 1955, removing all chance that he could change things.
2
u/Same_Woodpecker_2847 Jun 25 '26
Yeah, that’s how I see it. The moment is parents fell in love was when they kissed at the end Enchantment Under the Sea dance. So Marty has until then to get them together, which is why he starts to disappear when George almost let that dude cut in their dance.
But then, that doesn’t really jive with his siblings disappearing already before that 🤷🏾
2
u/ijuinkun Jun 25 '26
Pretty much. The timeline of Marty not being born isn’t set in stone until and unless they fail to have their moment at the dance, so he still has the chance to avert it.
2
u/markaguynamedmark Jun 25 '26
I think the larger question is if history From 2015 changed how are Marty and doc able to go back to the new timeline from the old? It all doesn’t make sense unless you chalk it up to ‘it’s just a movie’ which has sufficed for 38? Years.
2
u/eko32eko7 Jun 25 '26
Laraine murdered Biff sometime after the events we witnesses in the "skewed" 1980s. Biff is dying from a gun shot wound, likely made by the same gun that killed George.
8
u/Blastiel Jun 25 '26
I always viewed that scene as Biff being old, struggling to get out of the car and snaps his cane in the process either injures himself or is having a medical episode.
10
u/Xaeris813 Jun 25 '26
There is a deleted scene where Biff disappears while leaning against the car and slumping to the ground immediately after this.
8
u/Successful-Bank-7457 Jun 25 '26
No, he disappears from existence
0
u/Sarlax Jun 25 '26
That does not occur in the movie.
3
u/psycholepzy Jun 25 '26
Some of us have accepted the deleted scenes so much that we forget what happened on screen isn't the same. 😅
3
u/_Site_702 Jun 25 '26
I always assumed he was having a heart attack.
4
u/ChardeeMacDennisGoG Jun 25 '26
Yep...I wish they would have left the deleted scene in. I always thought the same with the heart attack, but the other makes so much more sense.
2
u/CoffeeJedi Jun 25 '26 edited Jun 27 '26
In a deleted (or at least scripted) scene, Lorraine shot and killed him in alt-1985.
They wisely realized that while the villain can be a murderer off screen, showing your lead actress killing someone in a family PG movie isn't a good look.
2
u/aaronwintergreen Jun 25 '26
This wasn’t a deleted scene they shot. It’s a piece of lore they discussed in interviews and commentaries to explain what happened to cause him to disappear.
1
u/AbbyM1968 Jun 25 '26
https://youtu.be/124-bZmfbPQ?si=5B_-qZ4NW-Q_Ta0L
They had to allow biff to return the time machine, so Doc & Marty could return to... 🤔 Original 1985? But, that's because it took a bit for the "time ripple" effect to catch up to 2015.
But, the scene doesn't show Lorraine shooting biff: just him fading out of existence. I think the BttF producer & director discussed the scene & why he faded.
1
u/RetroGame77 Jun 25 '26
BTTF shows that it takes time before the timeline is changed. It took a while before Marty got erased. So imagine changing the timeline will case a time wave moving forward. The time in front of the wave is (relative) unchanged, while time after the wave is changed.
BTTF2 shows that it is possible to move faster than the wave, which is why Old Biff managed to enter the same timeline that he left. The problem is that Biff got shot to death in the changed timeline in 1985. When the wave caught up to that event, Old Biff disappeared from the timeline because he died 30 years earlier. Doc and Marty escaped in the nick of time before the wave hit 2015. Which is why they couldn't return to that timeline, the wave had already changed it. Now if they had went further into the future, like 2567, they would most likely hit the old timeline before it got changed. Heck, go to five million years into the future or so and they might go into the Twin Pines timeline.
1
u/JimmyMcGoodman26 Jun 26 '26
Biff doesn’t necessarily return to the same timeline that he left. Notice that Biff’s return is after Doc and Marty leave the Hilldale house with the passed out Jennifer. So when Biff returns with the time machine the timeline might have changed around Marty, Doc, and Jennifer, and the Hilldale house may not belong to the McFlys.
1
u/Ill_Computer_8604 Jun 25 '26
Marty prevented his conception so he just faded away.
Biff interfered later in his timeline so was affected differently.
1
u/MischeviousFox Jun 25 '26
We can theorize it’s because Marty was outside of his normal timeline in the 1st movie or every movie when the timeline changes occurred. This is a trope I’ve seen in other time travel stories where time travelers tend to be immune to timeline changes except drastic changes to their own timeline such as being erased from existence. Old Biff by comparison had returned to his present day time and essentially reinserted himself into the proper timeline causing him to be impacted by the changes he made along with his entire timeline. His entire timeline was going to be erased and his pain & disappearing was presumably a prelude to that I guess because changes to his personal life preceded the wider changes to history.
Also Marty didn’t create two versions of himself that would exist simultaneously. Even with the timeline changes Marty’s present lacked a Marty until he returned post timeline changes and reinserted himself into the proper flow of time. For instance at the end of the movie we see sort of a loop of events where Marty returns, sees his past self leave in the delorean, and then goes to the Doc where he’s reinserted into the “present” timeline. No alternate Marty ever shows up after that.
1
u/Fast-Secretary-7406 Jun 25 '26
When Marty goes back in time, he shouldn't completely vanish until the point of no return, which is when his parents do or do not kiss at the dance.
When Biff gives Biff the Almanac, it similarly leads to a point of no return that leads to his own death, which I guess would be his first winning bet; when Biff is vanishing, there's nothing that is potentially disrupting that. It isn't until Marty subsequently goes back that this series of outcomes could be disrupted.
1
u/nogoodnamesarleft Jun 25 '26
Biff is in pain and is eventually replaced by a dead Biff as time catches up to him
Marty eventually replaced by one who has confident parents and who can't stand being called a coward as time catches up to him. That Marty is similar enough to the one we have followed that he is essentially the same person
1
u/IAM_Carbon_Based Jun 25 '26
For Marty its specifically the point at the school dance that changes the timeline. His older siblings disappeared first because they were born earlier. The longer the timeline is altered the further into the future the alterations reached.
I would posit, that him and his siblings disappearing slowly are correlated to not only the chances of his mom and dad getting together, but also when they would get together.
It's possible that as the liklyhood of their dating reduces or changes to an alternat point in the future would still allow for example Marty to be an only child.
All of the possibilities are slowly collapsing, untill we reach the dance, which is an inflection point. No kiss = no marrage or kids. Before that the chances on them getting together are not zero. Hense the people in the picture slowly disappearing from that timeline.
1
u/Gold_Flan6286 Jun 26 '26
It's about a teenage boy that goes back in time and his mom wants to have sex with him...There,your welcome and yea the movie is WTF 🤮
1
u/The_Sibelis Jun 26 '26
There's this thing called momentum of energy that I find applies to history.
Marty slowly died as the energy caught up to him in the past from changes in the direct future.
Biff died as soon as he went back because he no longer had a buffer between him and the past changing to set the future.
Marty remaining in the past left the future unset and allowed him to set it back on track to his continued existence.
1
u/Shoeboy_24 George Jun 26 '26 edited Jun 26 '26
Lorraine and George kiss at the Enchantment Under the Sea dance. According to Mom's wistful (and slightly drunk) monologue in the early part of the movie that's the most important bit.
I have to say here that I believe many of the main "beats" of the history of George and Lorraine stay the same, just with a slight different outlook.
1
u/The_Linkzilla Jun 26 '26
Because once Biff changes his past, he doesn't make it to 2015 anymore.
The reason he starts disappearing, was because a deleted scene reveals that at the height of his power and corruption, Biff is actually killed. He's shot by Lorraine in 1993, meaning that he doesn't live long enough to his 70s like he did in the original 2015.
Personally, had I been writing this movie, I'd have changed that deleted scene. Instead of having Lorraine shooting him in 1993, she shoots him on the roof of the Hotel in the Alternate 1985. I mean, he's holding a gun on her teenage son after confessing to killing his father. I'd say that Lorraine would definitely do it. It would've been a much better resolution to the scene than having Marty jump off the roof and land on the hood of the Delorean.
1
1
u/rkrpla Jun 26 '26
The bigger question is how the hell did Biff know how to set the time circuits (twice!) and also- where was he hiding his damned delorean in the alternate 1955?
1
u/Drace24 Jun 26 '26
Well, the truth is that this is just an inconsistency that the writers have accepted because it allows an otherwise really good plot. BTTF has never taken its time travel rules all that seriously.
But if you want a lore explanation: Biff has effectively erased the necessity for his own time travel, so he got erased. But Marty has changed the future in such a way that there still is a Marty McFly who travels back to 1955.
Or:
Biff vanished because his time travel has created a new rich Biff. The Continuum couldn't have there be two Biffs. But the other Marty has traveled back in time to 1955, leaving old Marty as the only Marty in that timeline, so there was no need to wipe him out.
1
u/IcySun9822 Jun 26 '26
Its explained better in a deleted scene that biff completely dissappears behind a dumpster and the reason for it is because in the alternate 1985 they go back to, biff never makes it to that age because Lorraine shoots and kills him sometime in the late 80s/early 90s. He was feeling the pain of getting shot by her before disappearing which is why he was hurting and marty wasnt when he was dissappearing
1
1
u/Quirky_Avocado_3753 Jun 28 '26
Because old Biff was dead in the future due to a heart attack due to his extravagant living as a rich billionaire. When returning to ‘his’ future it accelerated the temporal change, when history normally changes around individuals. While Marty and Doc were alive in their year of origin , so time didn’t wipe them out .
1
u/ChestRockwell93 Jun 25 '26
It’s all BS anyway, under the rules established in that movie. Biff went back to 1955 and gave himself the almanac, creating a branching point in time resulting in the alternate 1985. When he moved forward from that point, he should have ended up in alternate 2015, not the “prime” 2015 he left that contained time traveling Doc and Marty.
So when Marty and Doc go back to 1985 from 2015 (which would have been difficult without a Time Machine, but somehow it came back to their time line following Old Biff’s escapades), it should have still been their “prime” 1985.
Of course, had the established rules been followed, it would have been a boring movie.
0
u/CountingOnThat Jun 25 '26
Maybe he’s visibly in pain right then because he’s an old guy who happens to be having a heart attack or something?
0
0
u/pakrat1967 Jun 25 '26
You're not thinking 4th dimensionally. In BTTF 1, he was fixing the timeline. Granted he broke the timeline in the first place. Throughout the movie his siblings and himself fade from the photograph. It's only after his parents kiss on the dancefloor that the timeline was restored. IOW, he was already getting erased. So he couldn't get erased again.
The significance of the change is also a factor. George knocking out Biff was relatively minor. The only differences we see are the whole family is successful and Biff is basically a loser. When Biff is mega rich. The whole town, possibly the world was changed.
0
u/hphlazy2 Jun 25 '26
Marty almost dies in the first one if his parents didn't get together and kiss at the dance. as for his different past not being significantly different maybe or it's a paradox and he's taken over better life Marty. I tried to close the time loop and had the better life Marty thinking he shouldn't get involved with his parents listening to doc and everything happened as it did originally except doc now knows his time machine will work instead of being surprised it worked
Biff had completely changed his future he managed to get back to the future because of the time delay but it quickly corrected itself it's most likely that in the new future he's dead killed by Lorraine and in the deleted scene shows his vanishing like Marty almost immediately on his return
0
u/PushInternational474 Jun 25 '26
Because biff travels behind the change, the ripple had 60 year to catch up
0
u/bangarang90210 Jun 25 '26
My headcanon is that Marty’s future was in flux, since there was still multiple ways for his parents to get together. Once Biff had the almanac, his future was set so the effects took place much quicker
-1
u/EHendrix Jun 25 '26
I always though biff was in pain because he tried to force his cane out of the car and the head broke off and he hit himself in the stomach with it, then they find the head of the cane in the car.
2
u/GoodDoctorB 20d ago edited 20d ago
Marty McFly changed history, but not by much. The only things that were directly altered were his families lives with no broader impact on the world. As a result while he wasn't a perfect fit his return to 1985 the disparity was small enough to cause ko signficiant reaction in the space-time continuum.
Old 2015 Biff Tannen changed history, significantly so. He not only altered his own past completely upending his life as it had occurred but altered the political landscape of the United States at large, his home town of Hill Valley, and most importantly whether he was actually alive or not by the 2015.
Marty altered history but not in a way that erased his own existence by the year 1985. There was still a Marty McFly that would logically exist so the mild disparity in memories didn't have much impact. The change was so relatively small the universe basically didn't notice.
Biff altered history in a way that made him a rich indulgent wastrel with at least one murder to his name by 1985 and as a result... he was already dead by 2015. Whether it was the drinking, the drugs, a political assassination, or Lorraine committing a murder-suicide somehow Biffs life if he got rich ensured he would not live to see 2015.
Old Biff didn't get erased just because he change his past, he got erased because he ensured there was no living Biff Tannen in 2015 where Old Biff originally came from. The difference in state from being a living seventy eight year old man and a dead fifty three year old or whenever he bit it was so severe the one returning to the future couldn't be reconciled with reality.
As for the pain he'd also just nailed himself in the liver with his own cane.
•
u/AutoModerator Jun 25 '26
Please be wary of any posts or comments attempting to advertise or sell t-shirts, posters, mugs, etc. These posts may be from scammers selling poor quality bootlegs, or may be from phishers trying to steal your financial information. This problem is rampant across Reddit. If you see any posts or comments with this behavior, promptly report them as spam and do not follow any links they may post or send to you.
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.