Dr. Emmett Brown: [Doc has just finished the final preparations for Marty's return to 1985] Well, I guess that's everything.
Marty McFly: [pause] Thanks.
Dr. Emmett Brown: Thank *you*!
[Marty emotionally embraces Doc, which surprises him]
Dr. Emmett Brown: See you in about 30 years.
Marty McFly: I hope so.