Question: Marty prevents the bad 1985 by burning the sports almanac in 1955. However this alone won't prevent Old Biff from taking the almanac from 2015 to 1955. Indeed it raises the possibility that OB will remember having lost the almanac as a young man and choose to travel back to a date other than 12.11.55 to hand it over. I can think of three possible resolutions to this problem: (1) Marty makes a note of the date and time, then burns the almanac as a 47-year-old before Old Biff gets it; (2) Marty informs the 1950s Doc of what is to happen and he resolves to make the DeLorean more secure and/or not to throw the almanac in the bin; (3) Doc travels to 2015 in the steam locomotive and burns the almanac. Any other ideas?
Answer: I don't think it works like that. Old Biff came from a timeline that no longer exists, wiped out in favour of a timeline where his younger self becomes hugely rich because of the almanac, which is then ultimately replaced with a timeline where Marty wasn't involved in the car crash and he, and his children, are presumably more successful. In this new timeline, Marty and Doc would never have been to 2015 to try to sort out Marty's wayward children, Marty would never have bought the almanac, the old Biff of that timeline would never have learned about the time machine, and so would never have the idea of taking the discarded almanac back to his younger self, much less changing his date of arrival to try to prevent the theft. Doc and Marty have nothing to worry about.
Tailkinker
Question: One thing I never got is why Marty is so shocked that the Cubs won the World Series in 2015. He was then going to say something like "It's just that Miami..." but stops and asks another question. Was it ever said anywhere what he was going to say about Miami? That always perplexed me.
Carl MissouriChosen answer: The Cubs aren't exactly known as World Series contenders. Put it down to bad luck, but over 100 years, they only have one World Series championship. The last time they won the Series was in 1908, and the last time they were even IN the Series was in 1945. Being a Cubs fan myself, Marty's reaction isn't that much of a stretch. The Miami reference is because they didn't have a baseball team in 1985, which is all Marty knows of course. Since the movie was made, however, Miami has acquired an MLB team called the Miami Marlins (formerly the Florida Marlins).
Cubs FanQuestion: In BTTF III, the 1955 Doc is worried about sending Marty back to a "populated area" in 1885, so he insists on using the drive-in, which is way out of town. However, in BTTF II Doc repeatedly travels back and forth from 1985 to 2015 to 1985 in plain view of any number of onlookers. What could've caused Doc to stop caring if people saw his time machine appear and disappear into and out of thin air?
Answer: In 1985 and 2015 people would not have noticed a DeLorean on the streets, as they are used to seeing cars. By going to 1885, there was the added risk of people seeing a car decades before it was common, which would attract a great deal of attention and jeopardy to the time line.
TwotallQuestion: Just before eating the hydrated pizza, Marty says, "I missed that completely," and then nobody seems to want to take a bite. What did he mean by that, and why did nobody want to eat the pizza?
Matty BlastChosen answer: Bits and pieces were cut out of the dinner scene. When Marty says that, he's referring to a cut scene where Lorraine mentions that Uncle Joey was turned down for parole again. As for the pizza, no one does take a bite but it seems for reasonable enough reasons. Marty Sr appeared as if he was letting the pizza cool off, Marty Jr was trying to get fruit from the overhead fruit holder, and the daughter was answering the phone.
Answer: Claudia Wells, the actress who played Jennifer in the first film, dropped out of acting shortly after the film was made, apparently for unspecified medical reasons, only returning to acting in 1996. As such, she was simply not available to play the part.
Tailkinker Question: When Marty came back to 1985 in the first movie, some things had changed. The name of the mall for example went from Twin Pines Mall to Lone Pine Mall. How come then when Biff comes back to 2015 after stealing the DeLorean, everything seems the same? Wouldn't they notice everything was different when they were flying over Hill Valley to go back, like Biff's casino perhaps?
Answer: When Marty returns to 1985, he leaves 1955 after those changes have been made, so he's now in a timeline where the effects of those changes exist. When old Biff went back, he simply gave his younger self the almanac, then returned to 2015 before the younger Biff did anything with it, i.e. before any changes had been made. Old Biff therefore returned to his original unchanged timeline - the timeline split caused by young Biff using the almanac came after his departure, so he didn't enter the altered timestream.
Tailkinker Question: Doc knows all the timeline details of Marty Jr's movements on the 2015 day. So I assume to get this detailed of information, he had to have watched/followed him on that day. How come you never see the "other" Doc and time machine anywhere from Docs previous 2015 visit?
Answer: Because the Doc we're following would be careful to stay away from the path of the other Doc.
K.C. SierraQuestion: I never really understood at the end of this film why exactly Doc Brown goes back to 1885. Doesn't the DeLorean have to be going 88 mph for it to activate the system? The Doc was just hovering over Marty, so why did the time circuits automatically kick in?
Answer: If you look carefully, Doc accidentally knocks the time circuits on when trying to keep the DeLorean stable. When Doc and Marty were leaving the alternate 1985, we see that the time circuits were failing/faulty. So when the lightning struck the DeLorean, the time circuits were already on and with the equipment faulty, Doc was sent back in time. The DeLorean flips (possibly due to the flight circuits being hit by lightning) and the car accelerates to 88 MPH.
XIIIQuestion: What is the proposition that Needles offers Marty, which gets him into trouble with the boss?
Answer: The movie never states the details of the proposition. The audience is supposed to assume that Needles and Marty had previously talked about it off screen.
Brian C FriesnerAnswer: It's a plot hole. Biff couldn't have known or suspected the DeLorean's time-travel procedure, which necessarily included Biff setting the precise 1955 destination with no previous instruction. Biff just suddenly "knew" how to operate a time machine. He also changed the timeline by going back to 1955, so there's no way he could have returned to the "normal" 2015. But he does.
Charles Austin MillerIt's not totally impossible that Biff knew how to the time dial worked. He wasn't suspecting what it was, he knew it was a time travel machine and thus knew what the dial was for and possibly being technically educated knew how to use the time dial.
lionheadWe know from the first movie that Biff, by age 48, was waxing cars for a living in 1985. He hardly had a "technical education" and it's doubtful he acquired a technical education by age 78 in the year 2015. It was established in the first movie that he had become a timid underachiever.
Charles Austin MillerAlright I agree, he's not the sharpest tool in the shed. But he has lived for 78 years by then, till 2015. Even though he has no clue on how the flux capacitor works, he doesn't need to, all he needs to do is work the time circuits, a simple keypad system which even shows which display shows which time. For someone from 2015, it's not so hard to figure out.
lionheadChosen answer: He doesn't, but it's hardly difficult to work out - the date setting readout is pretty obvious. Biff presumably set the date, then just accelerated the car until the time circuits kicked in.
Tailkinker Question: The mechanic tells Biff the price of Biff's car is $300. Does that include the damage Biff caused to the truck he hit if the first film and also the price of the horse manure that had to be hauled away? I know Biff goes into a store across the street for a few seconds so we don't hear part of the argument. Wouldn't Biff have to pay more than $300, or was the $300 just for the car itself?
Answer: Remember that Biff's car was going very slowly and hit side on to the back of a much larger truck. It didn't damage the truck, it only caused the manure to come out.
LorgSkyegonAnswer: The mechanic does mention the horse manure in the dialog of the $300 but truck is not mentioned so it's unknown.
Answer: According to the actor's page on imdb.com, Wesley Mann's appearance as the "CPR kid" is his only role in the entire trilogy. He could be in another time period in an uncredited role, but it's more likely than not that his only appearance is in 1955.