Not all movie franchises have maintained a consistent continuity throughout all their installments. In fact, most movies can't make it through multiple entries without a plothole or two. While some movies might be deliberately and carefully planned to follow on from the vision of the originals, it’s common for a series to completely change direction in sequels, or for prequel movies to shed new light on events of the original film.

Often, the direction taken in a follow-up movie will require seeing its predecessor in a completely new light: it’s common for a movie to change continuity or play with the story’s timeline, making events in earlier movies either gain or lose poignancy. Here are 12 Movies That Dramatically Altered Their Franchise Continuity.

12. Star Trek

The 2009 reboot of the Star Trek franchise wants to have its cake and eat it. The movie is both a completely fresh take on the saga, and takes place in the same continuity (sort of) as the older movies and television shows. With Leonard Nemoy’s Spock appearing in the movie through some time travel hijinks, the film is able to tie together both the adventures of the original cast of actors from the classic ‘60s Star Trek television show, and the new actors. While doing so, however, it retcons much of the continuity within the original series and alters the Star Trek timeline for the rest of the rebooted series.

The events of the movie see time travel being used to dramatically to alter the lives of many key characters, including Captain Kirk, whose father is killed before he is born, and Spock, who sees his entire planet destroyed. With such dramatic changes to the movie timeline and characters’ backstories, it’s unclear how much the 2009 Star Trek will influence other key events of the franchise, including the upcoming new Star Trek television show.

11. The Lost World: Jurassic Park

The original Jurassic Park ties up all loose ends neatly in a line of throwaway dialogue from the park’s director John Hammond who, as the heroes flee the island full of rampaging dinosaurs, explains that all the monsters will die off in a few days without regular supplements designed to keep them alive. The ending quickly and efficiently closes off any lasting ramifications for a large population of dinosaurs being left alive on the Costa-Rican island.

Unfortunately for filmmakers, this single line also kills off any opportunities for sequel movies set on the same island – all of the original dinosaurs are dead. To fix this, the second movie in the franchise, The Lost World, explains that there was a second island which John Hammond neglected to mention, where all of the dinosaurs are able to survive without regular supplements – thereby completely undoing the resolution of the original movie, and making the affable park director appear fairly duplicitous.

10. James Bond

The Bond franchise, which features regular actor changes for many of its major characters, has never worried too much about continuity. With the Danial Craig era movies, though, the franchise has strayed further away from its old ways by telling the story of Bond’s origin – over the course of the four movies Craig has appeared in, moviegoers have visited Bond’s home, seen his loved ones killed, and even seen the rise of his most notorious villain.

Of course, not all of this backstory makes sense – not least because it heavily features characters like M, who were introduced far later in Bond’s incredibly loose timeline, and because the movie series started in the ‘60s while Craig's prequel-esque quadrology takes place in the twenty-first century. By this point it’s easier for fans to assume there’s no link between Craig-era Bond and the movies that came before at all, except for a few names and actors.

9. Prometheus

The continuity surrounding Prometheus is convoluted at best – originally designed as a direct prequel to Alien, the movie morphed into a more general story designed to build up some of the lore for the Alien universe.

Moviegoers learn about the origins not only of the alien xenomorphs and the Weyland Utani corporation, but also discover that the human race was originally created by an ancient alien species called the Engineers. Interconnecting all of these elements of the story casts a very different light on the events of the original Alien.

8. Halloween H20: 20 Years Later

By the time of H20, the Halloween series had seen six previous movies, which had featured various characters and had received mixed reviews at the box office. With the seventh movie, initial efforts were made to tie all of the previous movies together to form a consistent narrative – these plans fell through, though, and the movie instead chose to all but ignore the events of the three most recent movies, offering up a direct sequel to Halloween II instead, seventeen years later.

The movie didn’t entirely ignore the events of previous movies: Laurie Strode, played by Jamie Lee Curtis in all of the movies, is brought back for the movie after an off-screen death in Halloween 4 – it’s explained that the character faked her death in the earlier movie to start a new life away from the horrors inflicted upon her by her brother.

7. Superman Returns

Not all installments of the original Superman movie franchise were well received by viewers – while the first two movies received plenty of love from fans of the character, later movies in the series were less popular, featuring odd plot points and unbelievable fight scenes.

When it came time for Bryan Singer to direct a fifth installment of the franchise, instead of choosing to reboot the world as fans would later see with Man of Steel, the director chose to do his best to continue the earlier saga of films. Considering his own disdain for the third and fourth movies, however, Singer chose to banish them from the continuity of Superman Returns, instead electing to have his movie follow directly from Superman II. Retroactively removing two movies from the Superman continuity has a few problems for the story of Superman Returns, though – as at the end of Superman 2, Lois Lane has her memory erased, she shouldn’t remember ever having had a relationship with Superman (which is particularly problematic, as their intimacy led to the birth of her son).

6. Rise of the Planet of the Apes

The sci-fi classic Planet of the Apes has perhaps one of the most shocking plot twists in the history of cinema. Audiences at the time of its release were shocked at the discovery that Charlton Heston’s character, Taylor, has not crash landed on a distant alien world, but is instead on a dystopian future Earth, where humans have destroyed themselves and apes have become the dominant species.

While the original movie suggests that nuclear war was the cause of humanity’s destruction, Rise of the Planet of the Apes and its sequel, Dawn of the Planet of the Apes, provides a very different backstory for the events of the original movie. In the prequels, it’s not a colossal war that destroys human civilization, but rather a scientific experiment aimed at finding a cure for memory deterioration. Changing the cause of humanity’s destruction from nuclear hubris to disease is an interesting choice, which probably says a lot about society’s fear over its destruction in the modern era, compared with during the cold war.

5. Terminator Genisys

Time travel is a consistent theme in erasing past continuity to allow a franchise to travel in a new direction. With the latest installment in the Terminator series, the wibbly-wobbly nature of changing past events is taken to an extreme.

In the movie, it’s revealed that the events of the original Terminator movie have become so polluted by time traveling warriors from both sides of the future’s conflict that the events bear almost no resemblance to the plot that audiences are familiar with. Through retroactively introducing new characters and plot points to the events of the first Terminator movie, it was hoped that Genisys would revitalize the franchise – audience confusion and annoyance over the changes suggest that not all time travel soft reboots are as well received as X-Men: Days of Future Past.

4. X-Men: First Class

There have been plenty of inconsistencies between various X-Men movies which have led to a fluid continuity for the series long before Bryan Singer’s time traveling Days of Future Past came along to smooth over a few of the cracks in the timeline.

The prequel story explaining the origins of Professor X, Magneto and the first batch of X-Men did its best to stick to the existing continuity for the series: for example, opening shots from the original X-Men set in a Nazi concentration camp were recreated faithfully to add additional backstory.

With Mystique, though, Matthew Vaughn’s X-Men movie took some liberties, fleshing out the character substantially and giving her a strong familial bond with Charles Xavier. Based on this connection between the two, it’s odd when the two share screen time in X-Men and X2 and barely acknowledge each other – thankfully the two characters have so little time together in the earlier movies that this lack of dialogue is almost forgivable, but the events of First Class definitely change their dynamic throughout subsequent movies.

3. Back to the Future Part II

Not all changes to film continuity damage or harm the plot of previous movies. The Back to the Future trilogy is an example of filmmakers playing with the events of the original movie to add an extra layer of depth to the story.

In Back to the Future, time traveler Marty McFly attends a high school dance to try and convince his parents to fall in love. Through some light (and icky) incest and a few well timed punches on the part of Marty’s father, things work out for the best, even if a few things go wrong.

In Back to the Future Part II, however, Marty again finds himself at the same dance, this time trying to get his hands on a sports almanac which contains information that could destroy his timeline. The sequel weaves around the events of the first movie, as Marty has to simultaneously protect his past self from a group of goons whilst avoiding being seen. The movie adds nuance to the events that audiences are familiar with, and shows how the original Back to the Future is even more complex than viewers realized at the time.

2. Wes Craven’s New Nightmare

Freddy Krueger is one of the most iconic horror movie characters of all time, and his ability to cross the lines between dreams and reality make the character potentially very scary. In practice, though, his appearances have often ended up becoming very comical, and at times the character has come across as more of a pantomime villain than a supernatural terror.

This is perhaps why, in creating New Nightmare, director Wes Craven elected to break the fourth wall, with a plot that shows Freddy escaping from a movie to wreak havoc in the "real world." In doing so, the movie deliberately acknowledges that earlier movies in the franchise are fiction, thereby explaining away a lot of the silliness sometimes present in order to create a "but this time it’s for real" aspect of peril for the movie. Many of the earlier movies’ cast and crew, including Wes Craven himself, appear as themselves in the movie, further establishing the fourth-wall breaking premise.

This idea of horror stories bleeding into reality has proven popular – Wes Craven returned to the concept again for Scream, which saw murderers acting out horror movie tropes, and Tom Six made Human Centipede 2, which centers around a man who becomes so obsessed with the first movie that he decides to act out its events in real life.

1. Star Wars

While George Lucas claims otherwise, many fans suspect that his epic space opera wasn’t entirely planned from the beginning. Many elements present in later movies appear to contradict scenes from previous movies, or else make relationships far more disturbing.

Many fans maintain a high level of disdain for much of the prequel trilogy’s new insight into various aspects of Star Wars lore – this includes annoyance at an attempt to scientifically explain the Force, through technobabble about Midichlorians, as well as a loss of ambiguity over characters like Darth Vader, Boba Fett and the Stormtroopers, which many feel robs the original trilogy of its mysticism.

More controversial than any of this, though, is the ramifications of the Skywalker family tree. Fans were universally shocked at the reveal in The Empire Strikes Back that Darth Vader is Luke’s father, but were even more shocked when Return of the Jedi revealed that Luke Skywalker is the twin brother of Princess Leia. Considering that Luke definitely expressed physical attraction to Leia in the first movie, and that the two shared a passionate kiss in the middle installment of the trilogy, fans have hotly debated the extent of the pair’s incestuous relationship for decades.

Beyond this, of course, comes the larger questions of continuity which surrounds the original Star Wars movies – fans are divided over whether or not they should accept the changes that George Lucas has made to the Special Edition movies as canon. Considering the continued popularity of the "Han Shot First" argument, it seems not all fans are pleased with Lucas retroactively altering the continuity from his earlier works.

Conclusion

With an increase in the number of episodic movie franchises, and with movie studios looking to milk every possible drop of interest out of their properties, it’s not uncommon to see a movie series which grows far beyond its original scope and plot. Sometimes finding reasons to keep bringing back classic villains or settings becomes difficult, and it’s not uncommon to see plot twists in later movies which alter viewers’ understandings of events in earlier films.

Ultimately, though, the choice for how well these continuity changes are interpreted falls on audiences. Many viewers choose to be selective with which movies they consider their own personal ‘headcanon,’ and it’s possible to pick and choose which events they believe are relevant to the true story – after all, this list proves that movie studios have been doing exactly the same thing for years.