Back to the Future Part II

Plot hole: If Old Biff changed his past and went back to 2015, he goes back to HIS future, not the bad future, but Doc later tells Marty that if he were to go to the future to stop Biff from taking the almanac, he'd go to the bad future, so Old Biff technically shouldn't have been able to return to "his" future at all.

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Suggested correction: The effects of the past being altered may not have happened immediately. It is possible that it took time for the timelines to adjust to the changes of events, meaning enough time would have passed to change 1985 when they return, but not enough time could have passed to change 2015. By the time Doc says if they went back to 2015 they would be going to an alternate future, some time has passed, so the effects of the past being altered and taking ahold in 2015 and altering it are more likely to have occurred by then.

Casual Person

Here is what you say: "perhaps it took time for the time lines to adjust." What kind of time would timelines take? Time is time, it doesn't take time to change the timeline. That doesn't make any sense. Some people claim it was the DeLorean itself that came back to its own original timeline and only then reset itself in the new one, but then the new timelines being erased later on wouldn't have happened either. So its a genuine plot hole.

lionhead

It's established in the first film that it takes time for the changes to take effect. Marty and his siblings slowly disappear from the photo, rather than instantly. Although the scene in BTTF2 was deleted, it was filmed showing Biff dying and slowly fading away after his return to his present.

Yet they were restored instantly without any outside influence at the end of the movie. There are a lot of things wrong with this movie and the first one. Old Biff disappearing should mean that Marty and Doc should slowely disappear as well, even the DeLorean. But they didn't, that doesn't make any sense. The point is there is a plot hole, somewhere. To know where all you can do is look at it logically and then you automatically come up with Old Biff going back to the future but not the alternate future. If he did there wouldn't have been a movie, but that's the plot hole.

lionhead

The timeline didn't change until he made his first bet which was some years I think after receiving it. He immediately travelled forward after giving the act, meaning he will still jump forward to the original future.

The timelines would instantly change, and Old Biff couldn't possibly have returned to "normal" 2015. It's just a poorly-thought-out time travel plot hole (or a deliberate error to expedite the storyline).

Charles Austin Miller

Suggested correction: In context, Doc was saying that they couldn't return to 2015 to stop Biff from stealing the time machine, because Biff didn't steal the time machine in the alternate 2015, he only stole it in the original 2015. Marty and Doc didn't stay long enough in 2015 after Biff returned, and that's why they didn't see any differences. Also, though they were unaware of it, Biff was dead in the alternate 2015, so the disasters he caused might have reverted back after his death.

Plot hole: After Biff steals the DeLorean and travels back to 1955 with the Sports Almanac the movie states that he creates an alternate timeline. Doc Brown does a good job of illustrating this on a chalkboard. So if, as Doc Brown states, Biff created an alternate timeline, then when he travels back to 2015 it would be the alternate 2015. Even if the original timeline stays intact with Doc and Marty in it, they'd be trapped there because Biff took the Delorean and returned it to the new timeline, not the one they're in.

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Suggested correction: When Doc explains to Marty the events that changed the timeline from 1955 onwards, several hours have passed since they returned from the (original) 2015. Old Biff likely returned to the original 2015 not long after after giving young Biff the almanac, so it is entirely plausible that not enough time had passed for the alternate version of 2015 to take ahold. When Doc tells Marty if they were to go back to the future they would be going to an alternate future, enough time had passed for the future to turn into the alternate future.

Casual Person

Plot hole: When Old Biff goes back to 1955 to give himself the almanac, he comes back in the Delorean to the version of 2015 that he left, not the other, skewed version in which he is rich. Everything in 1955 should have changed around the Doc and Marty, as the Doc tells Marty everything will change around Jennifer and Einstein later on in 1985, when Marty and the Doc go back to restore normalcy. George is alive in this future, so we know the skewed version hasn't taken hold.

calgarry

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Suggested correction: It is established in the movies that the effects of the timeline being changed are not immediate. For example, in the first movie, in the photo of Marty and his siblings, it takes some time for them to vanish from it. When Doc tells Marty everything will change around Jennifer and Einstein when the timeline is restored, I don't think he meant the future will be restored to normalcy right that second, but more after an ample amount of time has passed for everything to be right. After Old Biff gave the almanac to young Biff, there was ample time for him to return to the original 2015 before it changed into the alternate 2015.

Casual Person

That would mean when they restored the timelines it would have taken time for it to adjust again, but it didn't. The new timeline was created but the old one remained because Marty and Doc were still in the original future. However, even though they are not in their original timeline it doesn't make sense for them to still be there, the timeline should have been erased or else old Biff wouldn't be erased either. Again though, a copy of another plot hole, which one is the oldest and original?

lionhead

Biff wasn't erased, he just had a heart-attack.

Goekhan

He was erased. It was cut from the movie, but the writers have said that it's still canon when asked in interviews why Biff was groaning (and the recent spin-off comics confirm it as well).

Back to the Future Part II mistake picture

Revealing mistake: In the scene where Doc Brown is following Biff into the tunnel, as Marty starts to pass between the cars on his hoverboard, one of the wheels on the rig supporting the hovering DeLorean is visible. (01:30:30)

More mistakes in Back to the Future Part II

Biff: Go ahead, kid. Jump. A suicide will be nice and neat.
Marty: What if I don't?
Biff: [raising gun] Lead poisoning.
Marty: What about the police, Biff? They're gonna match up the bullet with that gun.
Biff: Kid, I own the police. Besides, they couldn't match up the bullet that killed your old man.
Marty: You son of a...
[Biff pulls back on the gun's hammer.]
Biff: Suppose it's poetic justice. Two McFlys with the same gun.

More quotes from Back to the Future Part II

Trivia: In an interview, the director stated that hoverboards were real, but they weren't on the market because parents didn't like the idea of floating children. He said this as a joke, but this didn't stop mass hysteria as thousands of kids went from store to store looking for hoverboards.

moviedude345

More trivia for Back to the Future Part II

Answer: Yep, and there is, but they're both elsewhere. Doc's been committed to an asylum somewhere. When Marty first meets the alternate Biff, Biff tells him that he's supposed to be in Switzerland at boarding school - that's where the alternate Marty is.

Tailkinker Premium member

Wouldn't someone probably see Doc and report that he escaped from the asylum?

Maybe, but no way to be sure, and they're not around long enough for that to be an issue anyway.

Jon Sandys Premium member

Answer: Doc would most likely not have been seen by anyone, as the time he spent in the alternate 1985 was primarily inside the DeLorean, at a boarded-up library, graveyard, and his lab (and all at night too) so most likely not spotted by the public.

Even if someone had seen Doc, it could've been dismissed as someone who looks like him. Even if they did report his escape, someone would either call or go to the asylum and verify Doc was still there.

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