[sees Marty's picture, still thinking Marty is lying to him]

Pretty mediocre photographic fakery. They cut off your brother's hair.

I'm tellin' the truth, Doc. You gotta believe me.

Then tell me, Future Boy, who's President of the United States in 1985?

Ronald Reagan.

Ronald Reagan? The actor? [scoffs] Then who's vice-president? Jerry Lewis? I suppose Jane Wyman is the First Lady!

Whoa, wait, Doc!

And Jack Benny is Secretary of the Treasury!

Doc, you gotta listen to me!

I've had enough practical jokes for one evening! Good night, future boy! [slams door]

No, wait, Doc! The-the-the-the bruise! The bruise on your head! I know how that happened! You told me the whole story! You were standing on your toilet, and you were hanging a clock, and you fell, and you hit your head on the sink, and that's when you came up with the idea for the flux capacitor, which is what, makes time travel possible.