The encounter could create a time paradox, the results of which could cause a chain reaction that would unravel the very fabric of the space-time continuum, and destroy the entire universe!
— Dr. Emmett Brown (Christopher Lloyd)
9 seconds sound clip from the Back to the Future Part II movie soundboard.
You can hear this line at 00:26:05.586 in the Blu-ray version of the movie.
Quote context
[...]
- Oh, Great Scott! Jennifer could conceivably encounter her future self!
- The consequences of that could be disastrous!
- I foresee two possibilities.
- Granted, that's a worst-case scenario.
- The destruction might, in fact, be very localized, limited to merely our own galaxy.
- Let's go. I sure hope we find Jennifer before she finds herself.
- The skyway's jammed. It's gonna take us forever to get there.
[...]