We re-watched all 3 Back To The Future movies this weekend just gone. I’ve often thought: “I wish they could have done a fourth film. But how would they do it?”
Now I think I’ve just realised how. And it’s blatantly obvious.
In BTTF3, Doc leaves a letter for Marty, instructing him that he’s hidden the Delorean in a cave from 1885 and that he is to repair it with the help of 1955 Doc and return to his own present of 1985 – leaving 1985 Doc in the past.
Marty tells the Doc of 1955 that he fully intends on going back to 1885 to rescue Doc, and does so. Marty travels back to 1885, and the plot of BTTF3 unfolds as we see on-screen. But what about the second Delorean?
You see, Doc would have hidden the Delorean in the cave, just as he had before, so that future Marty would use it to return home. But in this timeline, Marty has altered the timeline yet again by going back to rescue Doc so that they both may return to their own timeline.
Now I’m going to stop here for a second. You see, in the confused world of Back To The Future, Doc specifically states in BTTF2 that when old Bif stole the Almanac, he created an alternate 1985 in which present-day Bif was mega rich, married to Marty’s mother . . . etc etc. So due to changes made by their presence in the past, Marty and Doc NEVER returned to their original timeline. When they went back to 1985 at the end of the first film, it was a different timeline (note the differences to Marty’s mum and dad). The same in BTTF3. It’s yet another version of 1985 that Marty and Jennifer return to, due to the changes Marty and Doc made in 1885 – notably the changing of Clayton Canyon to Eastwood Canyon.
So, in Back To The Future, alternate realities is the way. When Marty travels from 1885 to 1985 at the end of BTTF3, the Delorean (that was unearthed from the cave in 1955) is destroyed by an oncoming train. However the Delorean that was left back in 1885 is still there because it is a new timeline. In this timeline, Marty simply travelled from 1885 to 1985. He didn’t stop off in 1955. He didn’t go anywhere else but from the past to the present.
I would argue that, aside from the existence of a Delorean still concealed in an old cave, the three biggest flaws with BTTF3 are 1) When Marty arrives ‘back’ in 1985 at the end of BTTF3, everything would have reverted back to the way it had been at the beginning of the first film. 2) There would then have been 2 Marty’s in the one timeline, since in that timeline Doc wasn’t around to embroil Marty in his time-travelling adventures. So Marty could have in fact bumped into his own self, causing a time paradox. 3) Jennifer certainly wouldn’t have been on that porch, asleep.
So back to the Delorean. That’s how you make Back To The Future 4. It gets discovered by someone, done up, made to work, and there you have it: a whole new series of films, using the Delorean of the original trilogy to travel through time. Why hasn’t this been done yet?
And as for the flaws noted earlier: they couldn’t have followed that logic in the films, because it would have been one of the most depressing climaxes ever. Everything would have reverted to the shit state it was in at the start of BTTF1, with the added downer that Marty was now a prisoner in time, stuck in a world where he’ll forever be a doppelganger of his other self. No ride out to the lake with Jennifer.
So when do I start writing BTTF4, featuring all new characters? Where do I sign?
Tony Healey 
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