Franchises are funny things. There are times when the mere idea of adding to an existing story seems offensive; and there are times when not adding to it is heartbreaking. I roll my eyes at Universal’s idea of a monster universe; I can’t imagine Marvel without the MCU. Movies that don’t seem to need a sequel (Alien) sometimes get wonderful sequels (Aliens) and movies that are crying out for them (The Matrix) sometimes get terrible sequels. One TV show with hit or miss quality (Star Trek) might span several successful spin offs and movies; one largely fantastic TV show (The X Files) might stumble and fail to have any meaningful expansion. Sometimes it’s a lightning in a bottle sort of thing; how do you recapture the magic? The hoary old trope about inspiration and perspiration not withstanding, sometimes the magic just fails when it shouldn’t. But other times, there’s a reason for the failure.
How things fail
There are a couple of ways that a prequel can fail. The least pernicious path to failure is that the idea is just plain boring. Most stories start where they do for a reason, and if the events leading up to that story were that relevant, the story would have started there.
But boring can be forgiven; worse is when the prequel actively destroys the magic. You might wonder about the origins of a given character or situation, but most of the time, the sketchy picture your imagination is filling in is more satisfying than a detailed explanation. Lucas jealously protected the details of the Clone Wars in the early days of Star Wars‘ expansion into a shared universe, and the hints provided by Timothy Zahn and other authors painted a more horrifying picture of a galaxy wide conflict than Lucas gave us.
Even the injuries that transformed Anakin Skywalker into cyborg samurai Darth Vader are bland in comparison; we knew from the novelization of Return of the Jedi that a volcano world and duel with Obi-Wan was involved, but the details were vague. Mara Jade tells us in the Thrawn trilogy that Vader lost his right hand because he displeased the emperor. Vader’s transformation before the prequel trilogy was less a rush to save Anakin’s life and more a process of dehumanization, far more in keeping with the corrupting influence of the Dark Side.
You’ll see this, too, in Palpatine’s sudden transformation from charismatic chancellor to hideous emperor during his duel with Mace Windu, and it’s syptomatic of a larger issue with prequels: the need to explain everything. When you tie things up too neatly, the story loses some wonder and metaphysical veracity. Reality is a little messy. Stories that are too neatly tied up ring hollow.
Sequels aren’t immune to the problem of destroying the magic, but they have their own unique ways of falling apart. The most benign is probably the problem of power creep; as our heroes struggle to overcome insurmountable odds, they become more and more godlike. The worst offender in this regard, outside of the ultra-long form narrative of comic books, is probably Doctor Who. The Doctor has defeated so many unstoppable enemies that finding credible threats to him is hard. Now, in the defense of the highly uneven Moffat years of Doctor Who, Moffat at least recognized this issue and tried to do something interesting with it. It didn’t quite work, but that’s less a systemic thing and more a Moffat thing. Other examples include the USS Voyager repeatedly besting the Borg, and then the things that hunted the Borg, and then the things that hunted them. By the time that Star Trek: Voyager is over, the Borg have gone from being a threat to the entire galaxy to having all the threat of a pile of tribbles.
Worse is when the sequel doesn’t respect what went before it. Aliens succeeds, despite the HUGE change in tone from horror to action, because it respects what Alien did. Aliens 3, by contrast, kills most of the surviving cast from Aliens off screen and before the movie begins. The Last Jedi didn’t do that, but instead set about to intentionally deconstructing the movies that went before it and the characters that starred in it. In both of these cases, things could have been changed to make the movies work. Alien 3 could have been about someone who wasn’t Ripley. The Last Jedi could have chosen to develop its new characters without humiliating the old.
Chewing the Narrative Cud
Common to both sequels and prequels is the rehashing of old material. On one level, it feels like there is just an absolute lack of imagination in the world these days, manifesting as an endless cycle of reboots and sequels. It’s hard to say what drives this. I can see the fear that people won’t make a connection to the old material, and I can see cynical cash-cow milking. But let’s be honest: most of us are happy to return to familiar and loved franchises. We just want it to be done well. We want new adventures with old friends and familiar lands. It isn’t enough to just remake a beloved classic (A New Hope) with fancy effects (The Force Awakens).
How things succeed
The most successful sequels I can think of mix things up in ways that are logical. The largely wonderful classic Star Trek films launch with the premise that Kirk is now an admiral and hating it. Starships are his first love and now he’s a paper pusher. Over the course of the series, we see Kirk commandeering Enterprise, with nearly disastrous results; an older and wiser Kirk almost regretfully commanding against Khan; Kirk stealing the Enterprise to save Spock; Kirk and crew without that famous ship altogether. The Final Frontier might be an awful film, but at least we have the logical question of “Would a fresh ship really have the bugs worked out of it?” (The Undiscovered Country is an interesting anomaly; it’s a great film weighed down by an encroaching formula.)
Super Dimensional Fortress Macross is a war story with a love triangle front and center. Macross Plus is a love triangle (maybe more like a love pentagon) that shares the military trappings of its predecessor but with no war to fight. Macross Zero is a prequel that manages to be something new by involving new characters with a few old ones, and tells us a story sufficiently different that SDFM shouldn’t have started there.
The Vorkosigan Saga
Lois McMaster Bujold’s Vorkosigan books follow a noble family from a backwater world, Barryar, as it struggles to modernize. The first book actually follows the parents of the main protagonist, Miles Vorkosigan, and over the series we get everything from POW stories to mysteries to something wonderful that is halfway between a romcom and a regency romance. But the constant is that it all makes sense– Miles’ adventures in the military are when he is younger, healthier, more brash; as he begins to age and his adventure and deformities begin to take their toll on him, the stories transition with the character.
There’s no magic formula for success. The best writers sometimes turn out incredibly stupid ideas. But as with so many things, it seems like the path to expanding a fictional universe is a via media: navigating between disparate extremes. The successful addition to a narrative universe is connected, but not too connected. It changes elements, but does not alienate itself from other stories.