Davnes007 said:
Anchorhead said:
...I've always dug the Back To The Future handling of it - he goes back and does start to erase himself.....[etc.]
And then they did something weird in BTTF II.
"2015 Biff" steals the car, and takes the book to 1955....changes the timeline....and then returns to the original 2015.
...
If Doc and Marty couldn't go back to the original 2015 to stop Biff from stealing the book, how come Biff could return himself to 2015?
The ripple effect transformed 2015 around the time travellers. Keep in mind we only see 2015-A for a few scant minutes. It's after Doc retrieves Jennifer after seeing herself and, the main thing we see is the outside of the houses. In 1985-A it took Marty actually entering his house to realize things had changed. It stands to reason that they wouldn't notice subtle changes to the exterior of houses in 2015-A. It's established in Pt. III that the timeline does change around the time travellers. So, if they went to 2015-A all they'd be able to see is Biff returning. They'd never witness his intial theft of the delorean.
