Corrected entry: Marty and Doc need to go to Biff's casino hotel to find out the exact date of when old Biff gave the almanac to young Biff. However, the time circuits tell where they most recently were in time. So after old Biff came back to 2015 after stealing the time machine, they should have noticed that he had gone to 1955 to give the almanac away.
Corrected entry: The crashed Parkers' car is not the same car they had in first movie, when Jenn's dad came to take her - it has round lights, the previous one had rectangular.
Corrected entry: When Doc and Marty arrive in the alternate 1985, they drop off Jennifer and Marty goes to his house as if nothing is different (sans the bars Marty notices on her windows). But after Marty finds out it isn't his house, the streets are filled with destroyed cars, chalk outlines, gunshots are heard everywhere, and houses are on fire. Did they miss all this during the drive in? (00:38:52)
Corrected entry: As Marty and Doc fly away from Biffs hotel, Doc enters the Nov.12.1955 date then seconds later is shown to be switching on the circuits. Doc even says "Time circuits on" as he does this. The problem is that the circuits have to be already on in order to enter the destination date (as shown in BTTF 1).
Corrected entry: The old Biff gets the Almanac in 2015, steals the DeLorean, heads to 1955, gives the almanac to his younger self, and then heads back into the future, right? According to the Back To The Future way of explaining how time works and how events change the future, shouldn't he have gone back to the ALTERNATE future, instead of the future he left?
Corrected entry: In the scene where Doc is hovering the Delorean behind Biff's car, as Marty puts his feet on the hoverboard, the camera overtakes the Delorean, the driver of which is not Doc. Whoever it is simply puts his hand up towards the camera, to cover his face (but just slightly too late). (01:26:45)
Corrected entry: The money ratio in 2015 seems incorrect. When Doc sends Marty into Cafe 80's he hands him a $50 for a Pepsi. In another scene when Marty is walking outside, Old Terry asks Marty for $100 to save the clock tower. Usually a soft drink would cost more than what a man waving a can would ask for. Then when old Biff gets out of the taxi, his total comes to $174.50. According to the price of a Pepsi, doesn't this taxi ride seem cheap?
Corrected entry: In the DVD version, if you watch the deleted scenes, it shows old Biff Tannen returning to the future after giving himself the almanac and then being erased from history, probably because Lorraine shot and killed him in 1995. Here is the hugest paradox ever. If Lorraine shot and killed Biff in 1995, then how could Biff grow up to be old Biff and steal the Delorean and give his younger self the almanac in the first place? Also, immediately after old Biff gave his 1955 self the almanac, shouldn't old Biff have immediately been erased from existence while still in the year 1955?
Corrected entry: In the tunnel chase scene where Marty is on the hoverboard and Biff is in his car, after Marty gets the almanac, Biff drives to the end of the tunnel and spins his car around. The next shot is a close up of the front of Biff's car and you can clearly see his license plate. The year is supposed to be 1955, but his tags expired in 1951. (01:33:24)