When old Biff takes the DeLorean and goes back to the future, he comes back exactly to the same time and place he left, but according to Dr. Brown's explanation on the blackboard, he should have gone back to the new future he created, in which he has been rich all his life.

Why doesn't he appear in that new alternate future?

  • I checked before sending my question but him being in pain didn't really ring the bells for me. I guess it could have, since he is in pain from disappearing from the timeline, just like Marty in the first film.
    – Calabacin
    Commented Jun 13, 2017 at 8:11
  • This shouldn't be marked as a duplicate; it's a separate issue.
    – 2540625
    Commented Jul 8, 2017 at 21:57

1 Answer 1


From the Official BttF FAQ:

we believe Old Biff DID indeed return to a different future — a "2015-A," which would have transformed around Marty, Doc, Jennifer and Einstein (just as Doc explains how 1985-A would change into 1985 and instantly transform around Jennifer and Einstein). This would happen AFTER Old Biff returned with the DeLorean. For this reason, we made sure that Doc had caught Jennifer and exited the McFly Townhouse before Old Biff returned. Thus, by the time Marty and Doc are carrying Jennifer back to the DeLorean, there COULD be other residents in that townhouse — or perhaps the McFlys still live there.

As can be seen in Part 1, changes to the timeline aren't instant. So Old Biff traveled to a future that was in the process of transforming to the one he'd created. Only later do Doc and Marty notice these changes, by which time it's too late to go back to the future to fix them (Related: turns out Old Biff dies before 2015 in the new timeline, so he disappears shortly after arriving).

  • 2
    There's about three different answers on this site that use the same quote, but I didn't think any of them were specific enough about this question to VTC as a duplicate. Commented Jun 12, 2017 at 17:00
  • Thank you. I guess that makes sense. I wasn't convinced at first but it's true that these changes are not immediate, so I guess it's perfectly possible for him to go back to his own timeline right before fading forever.
    – Calabacin
    Commented Jun 13, 2017 at 8:10
  • 1
    "Doc explains how 1985-A would change into 1985 and instantly transform around Jennifer and Einstein." The key word is "instantly". All alterations of the past are fully realized once the characters return to the future. When Marty changes how his parents meet in the first movie, he returns to 1985 and finds everything about his family is different and better. Marty only sees the slow changes when he is altering the future from the past. Once he returns to the future it has already been set. Commented Apr 17, 2018 at 20:58
  • @DavidDeMar you might be right. It may be that it's just the time traveler himself that takes a while to change, while the world and the people in it transform instantly. Since this question was already marked as a duplicate, I don't think it's worth editing, and anyway the quote speaks for itself. Commented Apr 18, 2018 at 15:38
  • 1
    Plus, this raises the question of why Marty and Doc didn't disappear when the timeline changed, since Biff supposedly changed things enough that Doc was in a mental asylum and probably never even built the time machine or met Marty. Which is not something I want to break my brain thinking about. Commented Apr 18, 2018 at 15:42

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