Deliberate mistake: The 45's advertised as new releases on the record store sign actually came out at different times throughout 1955. A true selection of new releases from early November 1955 would have most likely included minor hit singles that 80's moviegoers wouldn't have recognized. The songs listed were some of the biggest hits of that year and were obviously chosen for their ability to help set the musical tone of the time. (00:34:30)
Deliberate mistake: In the beginning of the movie, we see Marty play his black Ibanez during the band try-outs. Later, we see it on his bed when Doc calls him and when he wakes up the next day in this alternate timeline. We never see him bring it home after school or when he goes home at night before dinner.
Suggested correction: Maybe one of the band members brought it back to his house for him. Maybe he forgot it and picked it up again later, off camera. Maybe he has 2. Maybe the guitar he is using at the try-out isn't his. So many possibilities.
Deliberate mistake: The sequence with the Libyans chasing Marty at the end of the film is much shorter than the original chase.
