Deliberate mistake: When Old Biff and Young Biff are sitting in Biff's car, the car's rear-view mirror vanishes during all shots of Old and Young Biffs together. Presumably this made the split-screen effect easier to do.
Back to the Future Part II (1989)
1 deliberate mistake
Directed by: Robert Zemeckis
Starring: Christopher Lloyd, Michael J. Fox, Lea Thompson, Thomas F. Wilson, Elizabeth Shue
Continuity mistake: Notice Marty's hair in the scene when he's playing "Johnny B. Goode." It's quite larger than when he says, some seconds later, "I guess that you're not ready for it yet." That's because when he says that, it's a recycled shot from the original BTTF, whereas most shots showing he's playing the guitar are newly made for BTTF2. However, Marty's hair is considerably longer in the new shots. (01:27:19)
Biff: Go ahead, kid. Jump. A suicide will be nice and neat.
Marty: What if I don't?
Biff: [raising gun] Lead poisoning.
Marty: What about the police, Biff? They're gonna match up the bullet with that gun.
Biff: Kid, I own the police. Besides, they couldn't match up the bullet that killed your old man.
Marty: You son of a...
[Biff pulls back on the gun's hammer.]
Biff: Suppose it's poetic justice. Two McFlys with the same gun.
More trivia for Back to the Future Part II
More questions & answers from Back to the Future Part II
Answer: At the end of the first film, Doc says, "what the hell" in response to the letter Marty gave him. So this shows it is not that strong a conviction, especially in the face of definite knowledge about something bad happening. It is also a way for Doc to repay Marty.
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