Corrected entry: In one scene, Doc Brown says that the year 1955 might be the junction point for the entire space/time continuum. 1955 WAS a big year for space travel, as it was the year that President Eisenhower entered America into a competition to send up a sattelite by 1957.(Our sattelite was called Project Vanguard; Russia won with Sputnik). Thus the space race actually started in 1955.
Corrected entry: Doc and Marty learn the date when Biff was given the Almanac. It turns out that this is also the date of the events in the first film. Doc then surmises that they will not only have to avoid detection by Old Biff but also by their 'other' selves. All that considered, does it not seem a little reckless to return to that date? They have a Time Machine, and the book is useless to Biff until he turns 21 which would be 1958 at the latest. That's a whole three years and Doc could have chosen from any day he wanted to retrieve the book but he picks the day where they run the greatest risk of screwing up time even more. Given that he's always lecturing on the consequences of messing with time, and that their entire future depends on him succeeding, it seems a little out of character for Doc to not even consider the possibility that they go back to a different day.
Corrected entry: After Marty burns the almanac in 1955, he looks at the newspaper that he has with him and sees that it is changing. One of the stories that changes is "Nixon to Seek Fifth Term; Vows End to Vietnam War by 1985" to "Reagan to Seek Second Term; No Republican Challengers Expected." Reagan wasn't looking for a second term in 1985 because he won it in 1984.
Corrected entry: As Marty sees his other self talking to his parents, Biff appears and challenges Marty to a fight. When Marty walks away Biff calls him a chicken. Marty walks up to Biff and when he says "Nobody calls me chicken" he gets hit by the door and even though you hear the word chicken, Marty's mouth doesn't move when he says it.
Corrected entry: You'll need slow-mo and pause for this one. When Griff's three mates throw down their hover boards they actually throw them beyond the camera, then digital super-imposed ones land in front of them. Watch closely at the girl's board (on the right) it's transparent, then the guy in the middle jumps beyond the camera and again super-imposed legs land on the hover board. (00:18:00)
Corrected entry: When old Jennifer and young Jennifer see each other in 2015, they faint. (Earlier on Doc mentioned that if they saw each other, either the space time continuum would stop, or something like that or they would merely faint.) This being so, then how come when old Biff and young Biff see each other in 1955, neither of them faint.
Corrected entry: In the scene where Marty is watching his other self talking to his parents (his other self just played Johnny B. Goode), he is watching through the door, when suddenly Biff turns up and they argue. When they are about three feet away from each other (just enough space for a door to be opened) you see Marty blinking his eye, because he expects the door to be slammed open, and the Marty from the first film rushes out.
Corrected entry: When Marty's daughter answers the door she lets in Grandma Lorraine and Grampa George. Lorraine says that she brought pizza for everyone. Marlene says "who's going to eat all of that" and Grampa George says "I will." Yet, when the pizza is hydrated, Grampa George is not in the kitchen at the table or in any of the following house scenes.
Corrected entry: When Doc and Marty are on their way to get the Jennifer of 1985 Doc says "Damn this traffic. Jennifer, that is the old Jennifer, usually gets home around this time." However Marty of 2015, when his mother asks where Jennifer is, says he doesn't know and that she should have been home hours ago. I don't think it took Doc and Marty hours to get to the house so Doc was way off with his calculation.
Corrected entry: Marty of 2015 is in the kitchen with his mother and two kids. We hear a phone ringing. Marty takes the call in the den and gives a verbal command "hello, in here please" as the words "incoming call" are flashing. After Needles hangs up we see and hear "thank you for using AT&T". Right after that, without any phone ringing, incoming call flashing, or Marty giving a verbal command to accept the call, his boss just pops up on the screen. Since the screen is two-way this would be an incredible invasion of privacy. The phone needed to ring and Marty needed to give a verbal authorization in order for his boss to be received.
Corrected entry: In 1955, Biff is told by Terry (the mechanic) that the bill for fixing his car after the manure accident was $302. Even deducting the $80 charged by Old Man Jones for hauling the manure away, that would be $222 just for a little bodywork and an inside valet. That's pretty expensive for today, let alone for 1955. I doubt that buying the car itself would have cost Biff much more than $300, especially since it's a 1940s model - so he can't have got it new. (Or perhaps he inherited it, along with the money he had: he lived with his grandma, so his parents were presumably dead). Since the same dirty accident befell him again later that very day, did he then try to minimize the bill by cleaning the car out himself? Perhaps that's how he got started on valeting cars for a living.
Corrected entry: Why is it that when in the first film when Doc grabs the door handle of the time machine when it comes back to normal time with Einstein in it and gets hurt by the extreme cold, but when he grabs the hood of the DeLorean in the second film to give Marty the walkie-talkie, he doesn't have a reaction at all?