Like all time travel stories, Back to the Future has several plot holes and time travel paradoxes, and these 13 are the biggest ones. Due to the nature of time travel and constantly changing timelines, Back to the Future has to keep track of a lot of small details, but some manage to slip through the cracks. Luckily, the Back to the Future trilogy has fixed some of these plot holes and paradoxes, although others are still in existence.
The Back to the Future trilogy mainly takes place in four different time periods. 1985 is the present across all three movies, while Marty and Doc travel to 1955, 2015, and 1885 throughout the trilogy. Due to the constant traversal between the past, present, and future, all kinds of alternate Back to the Future timelines are opened throughout the franchise, leading to some serious paradoxes. So, here are the 13 biggest plot holes and paradoxes from the Back to the Future series as well as which ones were fixed.
13 George & Lorraine Should Recognize Their Son As Marty McFly
One of the biggest plot holes in the Back to the Future series is that George and Lorraine McFly should have definitely realized that their son looked exactly like Calvin Klein in 1955. Although they didn't know Marty's alternate 1955 persona for long, he played a big role in both of their lives. Because of this, it is strange that neither of them ever mentioned how familiar Marty looked, although it makes sense that they wouldn't leap to the idea that Marty was a time traveler.
12 Marty McFly Shouldn't Have A Hairdryer In 1955
One plot hole that frequently gets brought up is that Marty McFly shouldn't have a hairdryer in 1955, although this has actually been fixed. In the first film, Marty puts on a sci-fi costume in an attempt to scare the 1955 version of George McFly. However, part of his costume is a handheld hairdryer, which shouldn't exist in 1955. The creators of Back to the Future answered this question, explaining that a deleted scene featured Marty pulling a hairdryer out of a suitcase that 1985 Doc put in the DeLorean.
11 The Clock Tower Should Work After Marty Gets Back To 1985
The broken clock tower is one of the most important elements of Back to the Future, with it ceasing to work after being struck by lightning in 1955. However, Marty and Doc change history by rerouting the lightning to Marty's DeLorean, sending him back to the future. Because of this, the clock tower should work when it is seen in Back to the Future Part II, although it is still broken for some unexplained reason.
10 Old Biff's Fate Was Never Revealed
A massive plot hole from Back to the Future Part II is that Old Biff's fate was never revealed, with him simply walking away after returning to 2015. This is another detail that is actually explained by a deleted scene. Since Old Biff gave Young Biff the sports almanac, this changed the future, meaning that Old Biff would cease to exist. Because of this, a deleted scene showed Old Biff falling over and fading away, although it was cut from the final film.
9 Marty Didn't Have To Steal The Almanac On November 12, 1955
The second half of Back to the Future Part II is pretty tense, with it following Marty as he tries to steal the sports almanac from Biff on November 12, 1955. Marty chooses this date because it is when Old Biff gives Young Biff the almanac, but choosing November 12, 1955, adds a lot of unneeded stress to the situation. Biff didn't use the almanac until several years after he got it, meaning Marty could have simply traveled to a time when it was unoccupied and taken it that way.
8 Old Biff Went Back To The Wrong 2015
Another paradox surrounding Old Biff is that he returned to his original 2015 timeline after giving Young Biff the sports almanac, but this actually shouldn't happen. Since Old Biff changed the future, 2015 should be completely different, but it looks the same when Biff returns. The creators have also explained this, saying that the timeline would either change around Old Biff or that the neighborhood he was in simply looked the same despite the timeline changes.
7 Old Marty & Old Jennifer Shouldn't Exist In 2015
Back to the Future Part II introduce Old Marty and Old Jennifer, introducing one of the series' biggest paradoxes. 1985 Marty and Jennifer meet 2015 Marty and Jennifer when traveling to 2015, but their older selves are from a timeline where they didn't travel to 2015. Since 1985 Marty and Jennifer did travel to 2015, this version of their older selves shouldn't exist and they should have been replaced by an Old Marty and Old Jennifer that did travel to the future when they were younger.
6 The DeLorean Time Travels Without Going 88MPH In Back To The Future 2
In Back to the Future II, the DeLorean time machine spins around before time traveling away, breaking the rule that DeLoreans must go 88 miles per hour to time travel. As it turns out, though, this problem has been fixed. Bob Gale and Robert Zemeckis have explained that the DeLorean doesn't necessarily have to be moving forward 88 miles per hour, and since it was spinning at that speed, it was able to time travel.
5 There Are Two DeLoreans In 1885
One of the franchise's most famous plot holes occurs in Back to the Future Part III's 1885 timeline. During the film, there are actually two DeLoreans in the same location: Marty's DeLorean as well as the DeLorean Doc used to travel to 1885. Although they are both broken, Doc and Marty could have combined parts from the two cars in order to make one that worked, solving the film's problems much faster.
4 Doc Brown Should Know About Einstein In Back To The Future 2
In Back to the Future Part III, 1955 Doc smirks when he learns that his future dog is named Einstein. However, Einstein was in the tape that Marty showed 1955 Doc in the first film, meaning that he should have already known this. This plot hole has also been fixed, with the creators explaining that Doc simply didn't see or this part of the tape.
