Continuity: When Marty (the Marty wearing the dark clothing) is at the dance and the Marty of 1955 is on stage is about to sing Johnny B. Goode, you can hear the 1955 Marty saying "this is a blues riff in B watch for the changes and try to keep up" through the microphone. Yet in the original, Marty looks away from the mike when he says this and is unamplified.
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Quotes
Marty: I don't get it, Doc. I mean, how can all this be happening? It's like we're in Hell or something.
Doc: No, it's Hill Valley. Although I can't imagine Hell being much worse!
Mistakes
When Biff is trying to get Lorraine to go to the dance with him, (the bit when Lorraine is looking at her dress) you see the same extra walking past her about three times. See more...
Trivia
In an interview, the director stated that hoverboards were real, but they weren't on the market because parents didn't like the idea of floating children. He said this as a joke, but this didn't stop mass hysteria as thousands of kids went from store to store looking for hoverboards. See more...
Back to the Future Part II (1989)
Directed by Robert Zemeckis, starring Christopher Lloyd, Elizabeth Shue, Lea Thompson, Michael J. Fox, Thomas F. Wilson (add more)
Back to the Future Part II mistakes
Continuity: In the beginning when Doc takes Marty and Jennifer to 2015 for the first time, they are descending towards Hill Valley. Doc turns the steering wheel to the left but the car goes right and down.
Continuity: When Marty is in Mr. Strickland's office trying to take back the almanac, it shows a wide view of the office with two flags right next to each other. After cutting to a close up view of Marty they are apart, then Marty moves them together.
Back to the Future Part II trivia
When Marty is waiting for Griff in the cafe he plays a videogame with two young boys. One of the boys is a very young Elijah Wood.
Vaguely interesting point - when Doc and Marty arrive back in 1955 to stop the handover of the Almanac, there are actually 4 versions of the same time machine in the area at that time. The one they've just arrived in from the alternate 1985, the one Marty arrived in from the original 1985 in the first film, the one Biff's arrived in from the future, and the one Doc's buried from 1885.
When Marty is scared because of the holographic picture of the shark coming from the 'Jaws 19' advert, if you look closely you can see 'Directed by Max Spielberg'. Steven Spielberg, who directed the first Jaws, has a son named Max.
Back to the Future Part II quotes
Doc: Roads? Where we're going, we don't need roads.
Doc: The time-traveling is just too dangerous. Better that I devote myself to study the other great mystery of the universe...women!
Lorraine: Biff Tannen, I wouldn't be your girl even if...even if you had a million dollars.