139

According to co-writer/producer Bob Gale: We never explained it in the movie. But the history of the characters that Bob Zemeckis and I created is this: For years, Marty was told that Doc Brown was dangerous, a crackpot, a lunatic. So, being a red-blooded American teenage boy, age 13 or 14, he decided to find out just why this guy was so dangerous....


75

There is a definitive answer to one part of this question: Is it likely that the producers simply overlooked this? No. It was intentionally removed from the original draft. (Obviously this version is fairly different) Here's the original ending of the script: INSERT – CLIPPING A story with the headline, “Police Quell Near Riot At School Dance,” along ...


68

I haven't seen any director commentary, so I can't speak with full authority. However, I don't think they thought that hard about it. I think it is put in there for dramatic effect. The antagonist was defeated, and now instead of the big man on campus, he practically begs from George McFly for work. It is a triumph of the little guy over his oppressor. ...


55

Even if they would notice, they would never accept it as a truth, because it is much against a normal understanding of the world. It would be probably like: "Ever notice how much Marty looks like that one guy I nearly fell in love with?" "Yeah, funny that". And thats it :). They could never imagine/reason, that Marty did time travel. So it is not even a ...


41

I think that, in the beginning of the film, Doc really doesn't have the letter. Marty's actions in the past changed our present, which is visible by the changes in the characters of Marty's family members and Biff, by the "pines" sign, etc. (image source) There is no reason for the letter to be an exception.


40

Remember that cat your parents took in for one week when you were a child? Isn't it strange that it looks exactly like the kitten you've been raising down to the last stripe? You don't remember what that cat looked like? I don't remember my childhood best friend's face very well and I knew him for years. Had I met him and known him for only a week I ...


37

The Doc Brown in 1955 is younger than the Doc Brown in 1885, by 30 years. The Doc Brown in 1955 will still live for another 30 years before traveling back to 1885 and being shot by Buford.


35

You do have a point in that the fuel could have been syphoned. However, it's more likely that there just wasn't any. When the doc gets back to 1885 with broken time circuits, he first tries to fix it. When he realizes it can't be fixed, he buries the car in the mine after first draining it of all fluids. While it is unclear if the car could be dug up, it ...


34

It's not clear that Biff was trying to rape Loraine. Although he was clearly taking liberties he should not have. McFly subdued Biff in the fight at the dance. After that, Biff learned to take his place behind McFly. The car-waxing scene was really just to prove this. 30 years had passed. The new, wiser McFly was undoubtedly able to forgive Biff--...


28

Yes. This is discussed by the creator of Rick and Morty in the Back To The Future documentary that was released recently. See the Wikipedia article on Rick And Morty. The series has its origins in an animated parody of Back to the Future created by Roiland for film festival Channel 101.


28

Bleeding Cool addresses this: In the Blu Ray commentary for Back To the Future, producer Bob Gale says: The opening shot, when the camera is going through Doc’s laboratory, there’s a newspaper on the wall that says the Brown mansion was destroyed in a fire. You can infer from that that maybe Doc set his house on fire to collect the insurance ...


26

What makes you think the lightning could strike before the clock tower was grounded (by Doc plugging the cables back together, the metal poles beside the road providing a path to ground). Things to note: When the plug near the ground pops loose, the free end is stuck in a tree, not too close to the ground, so not a great path to ground. Lightning is ...


25

The car had to reach a velocity of 88 miles per hour. It had nothing to do with the speedometer hitting 88 miles per hour. In the animated series episode Gone Fishin` Jules Brown (one of Doc Brown's sons) places a spare flux capacitor in a barrel. When the barrel falls over the waterfall and reaches 88 mph, the flux capacitor activities and moves Jules ...


23

I hope I don't spoil the party with an out-of-universe explanation, but I thought that this was really interesting when I found it out: It was just supposed to be funny. The sequels weren't written yet. In the commentary on the DVD, Robert Zemeckis and Bob Gale explain the scene, that it was all just there for fun, including the "To be continued…". At the ...


21

This is all just speculation, but some points to consider: How many bottles of this “petrol” would be required to get to 88 mph? To what degree is this “petrol” compatible with combustion engines from 1985? There were no highways back then, where could you find a place to accelerate to the required speed? (If I remember correctly, flight was not an option.)


20

There's no logic explanation for this, it's just a plot hole created by the need of giving more tension on the end of the movie. Maybe if the horizontal wire could stretch a lot while the car runs after the connection with the hook, but i doubt it.


19

In the original timeline, when the movie starts and Doc tells Marty to meet him at the mall, he doesn't yet know if the experiment will work. Time travel in Back to the Future works by changing history, and at that point, no one had time traveled yet. In the new timeline, shown at the end of the movie, it's unknown whether all of the 1985 events from the ...


18

Suppose the parents did notice the similarity. What would the chances be that they noticed exactly in the '85 time frames the movie shows? Nil.


18

We know that the timer went off several seconds before Marty floored the accelerator. We know that Marty quite literally hooked the line at precisely the correct time. Therefore the only valid conclusion is that Marty accelerated faster than Doc calculated/anticipated/intended. Thus there are only two valid explanations: (1) Doc planned for Marty to ...


15

It doesn't matter His parents never mention the similarity in the movie because: Before the 1955 part of the movie, it would be somewhat of a spoiler. After the 1955 part of the movie, it might have worked, but it would have been "cute dialog of convenience" and not really realistic there. Ultimately, if you accept the underlying premise of Back to the ...


13

They were going to try alternative combustible liquids. The first they tried was alcohol. The strongest one the could buy from the local bartender if I remember correctly. With that the intake manifold to blew out and then it would have taken about a month to repair it according to Doc. They didn't have the time for that since they were planning to leave ...


12

It's a paradox. Predestination Paradox to be precise. The Lightning only strikes the Clock Tower because of the changes Doc and Marty make in order to harness the power of the Lightning Strike. The exact time of the Strike didn't matter, because while Doc and Marty are aiming for that exact minute based on the paper/their "history", whatever they actually do ...


11

Who is to say they DIDN'T notice and comment on it... but we didn't see it? What would they have said anyway? Lorraine: Wow, Marty! You look just like a highschool friend of ours. (To George) Honey, c'mere! Look at Marty. Doesn't he look like that friend of yours, Kevin? George: You mean Calvin? Oh yeah, he does! Shame we don't have any photos ...


11

Quite simply, it was never fixed. Lightning from an electrical storm struck the lightning rod above the clock tower and travelled down a cable which was wrapped around the metal hands on the clock face at precisely 10:04pm on November 12, 1955. The sudden jolt of electricity damaged the clock mechanism and it has never worked since. The Hill Valley ...


11

There are two logical ways of dealing with time travel paradoxes: Stable time loop. When you travel to the past, whatever you do, you won't actually change anything (which pretty much implies there is no free will). In fiction, the way this is often done is that the time traveller attempts to change the past, but doesn't succeed, because it was him who ...


11

Marty was in the time machine when he came back. The definition of the time machine is that the machine (and what it contains) travel through time unaltered. (My real question would be, why is there just ONE Marty when he comes back to 1985 after fixing his family. There should be one Marty that was born from his parents on his normal birthdate, and one ...


11

Maybe, but the Post Office wasn't involved. The package wasn't delivered by the United States Postal Service, it was delivered by Western Union, a private company. Speaking as a former postal employee, I would expect them to lose it sometime in that 70 years. They may eventually find it... but find it and deliver it on time? Not likely. As a private ...


10

Because that wouldn't make a good movie. In reality they could have burned Kerosene that no doubt has a higher octane rating (150) than petrol of the time. With a low octane rating, they wouldn't have gotten to 88mph because the knock sensors would have cut timing and put the car in limp mode.


10

Whenever Doc Brown reaches an epiphany, he immediately sets to work to fulfill the context of said event. As an eccentric scientist, he has become accustomed to working in a high strung and over-driven manner, as he is always eager to have his projects come to fruition. With regards to what he concluded about Marty's children, he was alarmed by their ...


10

For an in-universe explanation: There may be sufficient capacitance in the system to allow the lightning charge to be stored for one minute. Doc Brown only knew the the lightning strike to +/- one minute, so it is logical that he would calculate the capacitance of the clock tower, and add additional capacitance to into the circuit to cover one minute of ...


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