how Marty and Doc became friends, and the absurd and strange friendship between a mad scientist and a high schooler is only appreciated for its odd sincerity. Thus, this dark theory with a murderous undertone seems hard to swallow.
Time travel is obviously a huge part of Back To The Future, and films involving time travel are innately complex. There is the possibility of crossing time-streams, creating paradoxes and ruinous butterfly effects. Thus, with so much to be considered, time travel films open up a plethora of fan discussions and theories. This particular theory concerns the first film, the ending of which sees Marty return to 1985 and witness a "new" Marty enter the Delorean and disappear, which is cause to wonder whether Doc had to do something dark in order to prevent a time disaster.
As detailed by a new Delorean in that timeline and get back if there was no Doc around.
In of how far Doc Brown would go to prevent something dangerous from happening with time, this farfetched theory might not be so inconceivable. Though he appears to be a kooky, harmless scientist, he has a past (or a future, depending on which lens it's looked at) of conferring with terrorists. Though he doesn't fund the terrorists, he, in turn, is essentially funded by them. This isn't morally ethical, and shows he isn't averse to darkness. Doc has also repeatedly used the Delorean for non-sensical reasons. He drums into Marty the importance of respecting the proper timeline, but in the second film (whichreshot the first Back To The Future's ending), he takes Marty and Jennifer to the future just because their future kids are bratty. He does, however, clearly care for Marty, as he's his only friend, which could be an argument showing that he wouldn't have the guts to hurt anything closely resembling him. However, Doc did firstly test out the Delorean time machine on his beloved dog, Einstein, possibly putting him in harm's way. This ambiguous morality and ever-changing code of ethics mean that harming or displacing the second Marty in the name of physics and time might not be a far stretch for him.
That being said, the Back To The Future universe abides by its own logic which could mean this dark Doc theory isn't justifiable. The film's universe itself deals with anomalies and potential paradoxes by simply erasing them, such as Marty in the first film. Furthermore, Back To The Future's time travel logic is likely not thought out so extensively as to make such a theory plausible. Whilst the film does feature a superficial degree of scientific accuracy because of its plot and Doc's character, the film isn't really built on physics. Rather, Back To The Future is built on heart, absurdity and a fun idea, and likely wouldn't make such a dark theory possible.
