And I fear that unnecessary time travel only risks further disruption of the space-time continuum.
7 seconds sound clip from the Back to the Future Part III movie soundboard.
You can hear this line at 00:09:03.927 in the DVD version of the movie.
Quote context
[...]
- Inside, you will find repair instructions.
- Once you have returned to 1985, destroy the time machine. Destroy it?
- Yeah. Well, it's a long story, Doc.
- And I fear that unnecessary time travel only risks further disruption of the space-time continuum.
- And please take care of Einstein for me. Einstein?
- He's your dog, Doc. Einstein is what you call your dog in 1985.
- These are my wishes. Please respect them and follow them.
- And so, Marty, I now say farewell and wish you Godspeed.
- You've been a good, kind, and loyal friend to me, and you made a real difference in my life.
[...]