Question: Doc has always been firm about not wanting to create some sort of paradox. Was he not at all worried that eventually someone would go into his barn looking for him and find his giant refrigerator and his model railway with the car that said "TIME MACHINE" on it? I know he stayed behind after he rescued Clara so could have removed all that, but the original plan was he was going to hop into the DeLorean with Marty. We know he definitely left the model railway there as Clara picked the car up which prompted her to go after him.
Question: When the 1985 Doc is suddenly transported back to 1885 at the end of BTTF 2 and Marty discovers that he has been murdered, because there is a Doc in 1955 that has already been born after the 1985 Doc has died in the West, why did he go to the trouble of going all the way back to 1885 when Doc was still alive? Is there any actual legitimate time travel reason for this, or did he just do it out of instinct to help his close friend?
Question: After Marty enters 1885, in his fleeing from the Indians, the DeLorean's fuel line gets ruptured and it loses all its gas. When Marty tells Doc this, Doc says gasoline doesn't even exist yet. However, Doc's DeLorean, which is now hidden in a cave, has its own gas supply in its gas tank and will not need it anymore, as 1955 Doc would just refill it after getting it out of the cave. Why didn't Doc siphon the gas from his DeLorean, and refill Marty's? He said the only problem at that moment was no gas. Not that he could not patch the fuel line, which would have been easy.
Question: At the end of the movie, Jennifer asks Doc about the note she got from the future that became erased when Marty did not participate in the race with Needles. Doc's answer to her question is that her future had not been written yet, and he goes on to say that no-one's future has been, but if that is so, then how come in the previous movies he could travel into the future with Marty to see Marty's future?
Question: For Doc to be so worried about corrupting the timeline in this movie (especially when it comes to falling in love with Clara) he surely doesn't seem to think twice about destroying the locomotive that will no doubt have a huge effect on the timeline. I doubt there were many trains on that railroad, with that mode of transportation now gone, Hill Valley itself could be wiped out.
Question: When Marty and Doc are on the train at the end, and Clara shows up, Doc says that Clara will have to go with them to 1985. Why does Doc say that? Someone submitted a correction saying that Clara is better off in 1885 because she was supposed to die so staying in her own period is better than going to the future, so why would Doc suggest such a thing?
Question: On the time traveling train there is the initials E.L.B, does anybody know what this stands for?
Question: Doc is a scientist right? The DeLorean had a ruptured fuel line and needed gas which, as Doc pointed out, was unavailable at the time. Surely he knew how to distill booze to make ethanol? (There was plenty of whiskey around at the time). I mean, they've used it to power cars in Mexico for ages. Why didn't Doc suggest this?
Question: When Doc comes back at the end, it's to say goodbye to Marty, but what's stopping him from just staying in 1985 with Clara and their two sons? I mean, before Clara turned up at the train in 1885, Doc was all set to go to 1985 with Marty, and then when Clara showed up, Doc said that they'd have to bring her too because there wasn't much time left before the train ran out of track, and he couldn't just let her perish. So why doesn't he just stay in 1985 - that's where he was going to go before Clara turned up, and now that he has her, and a family, why not just settle down in 1985?
Question: I have a question, I don't know if it's true or not but I have heard about this for years after Part III was released. Had Crispin Glover decided to do the sequels, would he have had the role of Shamus McFly in Part III, or once Glover turned down the sequels, then it was decided that Michael J. Fox would play the part of Sheamus once Part III was greenlit? Or was it always going to be Fox playing the role of Sheamus regardless if Glover came back for the sequels or not?
Question: On the movie timeline website it says that on November 6 2012 America elected a female President, and that this fact comes from Back To The Future Part III. Where in the film is this mentioned?