Biff Tannen: [after tripping a scientist] Have a nice trip, see you next WINTER!
Biff Tannen: [after short-circuiting the lab, and trapping Doc in his own office, he knocks] Hello! Hello! Dr. Brown!
Doc Brown: Biff! How in the blazes did you get here?
Biff Tannen: [revealing the tied up scientists] Why don't you ask these bozos?
Institute Scientist: [Biff removes the tape off of the scientist's mouth] Dr. Brown. Our team was conducting an experiment back in 1955.
Female IFT Scientist: He must have stowed away!
Biff Tannen: Hey! I'm not the one to pass on a free ride!
Doc Brown: Go fourth time travelers, and remember the future is what you make it!