Time travel, as presented to us by Back To The Future, is basically a good deal: You get a hoverboard! You get to teach a gang of '50s teenagers how to rock! You get to drink sodas at completely un-ironic diners! But while a DeLorean ride through time may seem all fun and games, there's a grim fact at its center.


After reading this comprehensive ranking of time travel movies, a discussion began about the movie at the top spot, Back To The Future.


At the end of Back To The Future, though we're only following one Marty, the movie has essentially created two: one that grew up in the original timeline and one that grew up in the alternate. So just what happens to that other Marty?

Mweyer Interesting how "Timecop" and "Back to the Future" share the same underlying horror ending: Marty and Walker both have no memory whatsoever of the great lives they've had in these new futures and so everything is going to be strange around them. I admit, it does kind of bug me. I mean, how many times will the McFlys mention some great family bit and Marty just brushes off "oh, yeah, right" without them noticing he's not into it? I know, plenty of holes in the film as is but that still bugs me. MarlowePI I rationalize it as there being a delayed effect to his memory, kind of like the picture and him gradually fading away as changes to his parents' history were made. This is supported — for me, anyway — in the second movie when he and Doc treat the 1985 the first movie ends with as the "real" 1985. commandersalamander Another disturbing possibility is that Doc Brown, by the end of the first film's 1955, knew that he would invent the time machine and that he had already sent Marty back to an altered future as he saw the improved version of George McFly grow up. Years later, he befriended the new, well-adjusted, well-to-do "Marty 2" under false pretenses, only to send him to his likely death in a sabotaged time machine in Oct 1985, thus clearing the timeline for the return of the original Marty.

And the problem isn't limited to just Doc and Marty, characters who didn't make the trip may find their timelines getting messier, too:

euge04 BTTF II is a great movie but the time travel logic is messed up. How does old Biff return to the decent future where Doc Brown and Marty are? The Doc should have to rebuild a new time machine to go back in time to get to the point before Biff got there. I like to believe once they change the timelines they create an alternate timeline and can never return to the old one unless they go back to before they left. Of course this creates a new alternate timeline. But all the people in those old alternate timelines do not cease to exist. Marty and Doc just no longer exist in those timelines. So really that means that Jennifer should be stuck on the porch in the crappy 1985 and was left behind by Doc and Marty. I always wanted to do a one-shot comic where she wakes up and has to become pretty badass to survive. It would make a good movie too.


What do you think? Do you have any theories about how the alternate and parallel timelines worked out in Back To The Future? Tell us them, along with timeline spinoffs you're dying to see onscreen, in the comments.