Back to the Future

Corrected entry: When Marty shows Doc the flyer from 1985 about saving the clock tower, this gives them the time that the clock will be struck by lightning, 10:04pm on that coming Saturday (11/12/55). However, the main problem here is that the time is only given in hours and minutes, and since lightning moves at the speed of light, an entire lightning strike lasts only fractions of a second. Doc and Marty have no clue as to what second the lightning will strike during that minute, and it isn't given a thought. In reality this would cause a tremendous dilemma if the Delorean had to pass at a precise second. And since the clock on the tower lacked a second hand, they would need a sychronized watch to determine the second the strike occurs, even if they knew it. In the movie it is assumed the strike occurs at 10:04:00, which is fine, but for more realism they could've added a second hand to the clock to eliminate this plot hole. It would have been stuck in place as the other hands after the lightning strike.


Correction: A second-hand isn't necessary. The second within the minute that the lightning strike occured could have been been determined by an examination of the inner workings of the clock (which stopped functioning after the strike). Such a noteworthy piece of trivia would likely have been included in the Hill Valley Preservation Society's flier. In fact, Doc states as much - that according to the flier the clock is struck at precisely 10:04pm.

JC Fernandez

Even if they examined the insides of the clock and reported the precise second of the lightning strike in the flier (which is itself improbable), they would only know the time down to the nearest second (and that's assuming the clock tower kept perfect time). 88 miles per hour is about 129 feet per second-at that speed, even being off by a few milliseconds would cause the lightning to miss the DeLorean entirely.

Corrected entry: When Marty shows the video to the 1955 Doc, the 1985 Doc on the video states their location as the "Twin Pines Mall". Since Marty already knocked down one of the pines, the mall should've already been renamed to "Lone Pine Mall" on the video.

Correction: The timestream in the Back To The Future series is demonstrated as being somewhat resistant to changes; when Marty interferes with his parents' first meeting, he doesn't start to fade out for about a week after that happens. When Marty shows Doc the video, not enough time has passed for the effects of the timeline change to appear on the tape.

Tailkinker Premium member

When someone time travels, they don't change the timeline they are from, they just create branching timelines every time someone makes a decision. This recording was made in the first timeline, so it would still be Twin Pines Mall.

That's not the case though. The photo Marty brings of his siblings fades out, newspaper headlines brought from the past/future change, etc.

Except he was slowly disappearing at the end of the movie. Which wouldn't happen if he was "branching off." They mix up linear timelines and parallel universes in these movies. They always, always screw up time travel movies.


Corrected entry: Even with Marty's brief instructions, it is near impossible that each backing band member (each, and as a whole) could have pulled off a near perfect rendition of Johnny B. Goode, not ever having rehearsed, known or heard the song, etc.

Correction: 1. It is NOT a perfect rendition. 2. "Near impossible" is not impossible. 3. This posting renders every musical ever made impossible.

Also, Johnny B Good is a three-chord song. Any musician, especially one in a professional band, could follow the pattern, knowing the key.

Corrected entry: Anyone else find it ironic that Einstein the dog was the world's first time traveler, while the real Einstein was the one who said that time travel is impossible?

Correction: Part of the "strange" world that Einstein explained in 1905 in his theory of relativity is that time and space are joined in our universe as a four-dimensional fabric known as space-time. Stranger yet is the concept that both space and time warp as mass or speed is increased. Einstein actually proved that time travel was theoretically possible, then spent the rest of his life trying to disprove it.

Corrected entry: In the scene where Marty is playing Johnny B. Goode, and someone cuts into George and Lorraine's dance, Marty starts disappearing. Then he comes back, pushes the guy down, and kisses Lorraine, resulting in Marty reappearing. But George did that on his own, without Marty interfering, so why should he have disappeared in the first place? He was always going to come back and assert himself - it's not like the timeline was being changed.

Correction: According to the films, the future is never set. For instance, in the third film, at first it's Doc's name on the tombstone, then no one's name, then Marty's name starts to appear, then finally the tombstone disappears altogether. This happens in response to how Doc and Marty act and make decisions. The same idea applies to the dance- when it looks like George is just going to walk away, Marty's existence is in danger, but when George changes his mind and returns to Lorraine, the future has changed, and Marty's existence is secure.


Correction: If you look at the time readouts, Marty travels to Nov. 12, 1955 at around 6 am. What time it was at the moment didn't matter.


Corrected entry: Mayor Red Thomas in the 1950s based on his picture, looks to be around age 50. However, in 1985, when he is a bum, he still looks about the same age, even though he should be around 80 years old now. Granted, some people age better than others, but it is doubtful that an old man living on the streets would even survive for very long, let alone age gracefully.


Correction: You are assuming Red has lived on the streets for a long time. We have absolutely no information about how long he has been a bum; he could just as well be a youngish-looking 80-year-old who just recently suffered a decline in fortune and became homeless as a result.


Red the homeless guy is not former mayor Red Thomas. Bob Gale said that Fox improvised the name on the day.

Corrected entry: At the beginning of the film, when Marty gets to the Doc's place he is wearing a watch, so he could easily know about the right hour in spite that the clocks are wrong.


Correction: 3 possibilities from the top of my head: 1. He wears the watch but never checks it, it's just a fashion statement for some people, next to that he just entered a home with a wall full of clocks, no need to check your watch as well. 2. The watch isn't working (it's digital). 3. The watch could be on the wrong time as well.


Corrected entry: After Marty returns to the present, he wakes up in his room that is identical to the beginning of the movie, however the rest of the house i.e the living has changed and is more modern.

Waldo Gonzalez

Correction: That merely tells us that Marty was more or less the same in both timelines, having similar tastes.

Which wouldn't happen. Because with loving, successful and self confident parents, there's no way a kid turns up just the same as with goofy, drunk, and pushovers parents.


Unlikely, but not impossible and therefore, not a mistake.


Corrected entry: When Marty first enters Lou's cafe in 1955, Lou is visibly angry at Marty just because he won't order something right away. However, he doesn't seem to care that one of his paying customers, George McFly, is being harassed by Biff and his gang and told never to come in there again. You would think Lou would tell Biff and Co. to knock it off or else be asked to leave.


Correction: George had already paid for his cereal, what does Lou care? Biff and Co. are paying customers on occasion too, he wouldn't want to alienate them either. Especially considering they're likely to vandalize his restaraunt in retaliation.

Phixius Premium member

Corrected entry: When Doc is on the clock tower in 1955 during the storm, a closeup of his feet is shown. He is wearing shoes with velcro straps in this shot. Velcro did not yet exist in 1955, and Doc had not yet traveled into the future.

Correction: The concept behind Velcro was conceived in 1941, the idea was submitted for a patent in 1951, and the patent was granted in 1955. Not impossible that Dr. Emmett Brown, a member of a wealthy family and fellow inventor, could acquire some.

Phixius Premium member

In a deleted scene the Doc is shown going through his future self's belongings and finds the Velcro shoes in his luggage along with the hairdryer that Marty uses as "Darth Vader." Doc simply "stole" the shoes from himself.

Corrected entry: Wouldn't Marty's parents and Biff Tannen be amazed and freaked out that their son Marty is identical to Calvin, the kid that played a major part in all their lives, and who they would definitely remember?


Correction: It's 30 years later, I doubt they remember a guy who they only knew for a few days back when they were teenagers well enough to recognise him as Marty.


Besides they don't know about the time machine. To them, it is a coincidence at best.

Corrected entry: When Marty is trying to prove his futureness to Doc, he says that his sister was in the class of 1984 and then shows Doc a picture. Whenever the picture is shown however, the shirt says class of '81.

Correction: There's a vertical fold in her sweatshirt causing the '4' to be compressed so it looks like a '1' if you don't look too closely.

Corrected entry: This one is tricky but important in view of Doc's concern about doing anything that will alter the future. The lightning rod on the clock tower would have been connected to ground with a thick cable. Doc would have had to disconnect this cable to allow the current from the lightning to flow into his cable instead and hence to the time machine. We now know that a lightning strike is a result of a complex interaction of electric potentials between charges in a cloud and charges in the ground below. By disconnecting this grounding cable this interaction would have been disrupted, causing the lightning to strike at a different time or strike a different object on the ground.

Correction: If you touch a lightning rod while lightning strikes it, you will still get electrocuted. So, just like the energy would travel into your body, it traveled through Doc's cable. No need to disconnect the ground. If grounding a power source kept it from charging any thing else, no electrical appliance would ever function.

Phixius Premium member

Corrected entry: When Marty travels back to 1955 the DeLorean first strikes a scarecrow, then drives at high speed into a barn and finally crashes through the barn door to escape. Later, when it returns to 1985, it crashes into a movie theatre front before it can stop. After all this mayhem the DeLorean doesn't have as much as a scratch on its nose.

Correction: That's because the entire body of every DMC DeLorean is made out of stainless steel, not fiberglass.

Phixius Premium member

Corrected entry: After Marty returns to 1985, he discovers that he now has the new Toyota truck he wanted, while the rest of his family is forced to share one car. Why would Marty, the youngest of the siblings, who is still in high school, have his own brand new truck while his older siblings and both parents have to share one other vehicle?


Correction: We only see one vehicle other than the truck, this does not mean it is the only other vehicle. We only know that Marty's older brother uses the car to go to work.

Phixius Premium member

Corrected entry: After Marty reunites his parents, he and his siblings all reappear in the photo and all is well. However, in order for Marty and his brother and sister to exist again, it would mean that Marty's parents would have to have sex at the exact same moment all three times to conceive them. Even if they were a few seconds off, it wouldn't be the exact same three kids. Similar maybe, but not exact. Now that George is more successful, he will be doing many things differently in his life so the chances of him and Lorraine having sex at the exact same millisecond all three times to have those exact three kids is beyond astronomical.


Correction: This is purely speculative. There is no way anyone (other than the filmmakers) can say what "should" have happened in the altered timeline. The odds may be astronomical, but the odds are certainly better than the odds of a plutonium-powered, time-travelling Delorean being invented.

JC Fernandez

Correction: "VODKA" (at the bottom of the label) is not spelled backwards. I think you're confusing it with the brand of vodka, POPOV. Only the last few letters are visible in the shot. ("-OV").

JC Fernandez

Corrected entry: When Doc is having the DeLorean do the burn out to get the car up to speed, the car is spinning its wheels up to 65 mph and Doc releases the brake. Now the car takes off, but the car would lose most of the speed the tires had built up as it is starting from essentially a dead stop even though the speedometer still shows 65 mph. Think of it this way, the back tires may be moving at 65 mph but the front tires are not. There is no physically possible way for a car to jump from 0 to 65 mph instantaneously using only its tires no matter how fast they were rotating. Even an F/A-18 needs a catapult to get that kind of speed so quickly. (00:21:35)

StopNGo & Girls

Correction: If the speedometer was hooked up in such a way as to show 65MPH as the speed before the brake was released, it would still show it afterward. The car was never going 65, true, but the tires were telling the speedometer it was. For whatever reason this is how Doc wired it all together. The tires wouldn't slow down suddenly just because the brake was let up, they'd continue to skid until the car's speed matched their own.

Phixius Premium member

Corrected entry: When Loraine tries to kiss Marty in the car and he pulls away, she asks if something is wrong, but instead of calling him "Calvin" (as in Calvin Klein) she calls him "Marty."

Correction: When Marty first met her, and she thought his name was Calvin Klein, he told her his friends called him Marty. She referred to him as Calvin and then Marty in the scene in Doc's garage, and she calls him Marty in their last scene before he goes back to 1985. Clearly she's getting used to calling him Marty.


Continuity mistake: When Marty chases after Biff on the borrowed 'skateboard', Marty is wearing a dark grey belt and a red/blue print shirt under his red/beige jacket. However, when Marty is hanging on to the front of Biff's car as they turn a corner (and in another shot), Marty (stunt double) is wearing a light brown belt and solid tan shirt. (01:07:00)

Super Grover Premium member

More mistakes in Back to the Future

Marty McFly: Calvin? Why do you keep calling me Calvin?
Lorraine Baines: Well, that is your name, isn't it? Calvin Klein? It's written all over your underwear.

More quotes from Back to the Future
Back to the Future trivia picture

Trivia: Eric Stoltz was originally cast as Marty. After filming quite a few scenes they realised his acting style was too dramatic for the humor desired, so they cast Michael J Fox (who they couldn't originally get because he was busy with the TV show Family Ties). Filming was on weekends and nights around his TV schedule and using his double at other times.


More trivia for Back to the Future

Question: What is the make/model of the car that Biff wrecked, that is being towed into the McFly's driveway near the beginning of the film?

Answer: The car being towed into the driveway is a 1979 Chevrolet Nova.

More questions & answers from Back to the Future

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