Doc: "Date: Sunday, November 13th, 1955, 7:01 a.m. Last night's time travel experiment was apparently a complete success. Lightning struck the clock tower at precisely 10:04 p.m. sending the necessary 1.21 gigawatts onto the time vehicle which vanished in a brilliant flash of light leaving a pair of fire trails behind. I, therefore, assume that Marty and the time vehicle were transported forward through time into the year 1985. After that... After that, I can't recall what happened. In fact, I don't even remember how I got home. Perhaps the gigawatt discharge coupled with the temporal displacement field generated by the time vehicle caused a disruption of my own brain waves, resulting in a condition of momentary amnesia. Indeed, I now recall that moments after the time vehicle disappeared into the future, I saw a vision of Marty say he had come back from the future."
Marty McFly (Michael J. Fox): "Hey, Doc?"
Doc: "Undoubtedly, this was some sort of risidual image. (screams in horror)"
Marty: "(screams in reaction)"
Doc: "(leaning on the organ)"
Marty: "Doc, calm down, okay? Just calm down! It's me! It's Marty!"
Doc: "No! It can't be you! I sent you back to the future!"
Marty: "That's right, Doc. That's right. But I came back again. I came back from the future. Dan't you remember last night? You fainted. I brought you home!"
Doc: "This can't be happening! You can't be here! It doesn't make sence for you to be here! I refuse to even believe that you are here."
Marty: "Doc, I am here, and it does make sense. Look, I came back to 1955 again with you, the you from 1985, 'cause we had to get a book from Biff. So, once I got the book back, you, that is, the you from 1985, were in the DeLorean and it got struck by lightning, and got he sent back to 1885!"
Doc: "1885? It's a very interesting story, future boy, but there's just one little thing that doesn't make sence. If the me of the future is now in the past, how could you possibly know about it?"
Marty: "You sent me a letter."