Why is Hollywood building so many cinematic universes?

It feels weird to open with a spoiler warning for a medical drama from the 1980s, but if you're particularly sensitive to plot details from St. Elsewhere, you might wish to skip to the first sub-heading.

The infamous season finale placed all of the characters and events that had preceded it in the imagination of one of the doctors' autistic sons, Tommy Westphall, who dreamt it all up while staring into a snow globe that contained a replica of the hospital where it all took place. The funny thing is, St. Elsewherehad crossed over with other American TV shows, including Homicide: Life On The Street and Cheers, meaning they also potentially took place in Tommy's imagination.

Extrapolating on an argument advanced by the late, great comics and television writer Dwayne McDuffie, fans have charted the inside of Tommy's imagined universe, and have posited that it encompasses everything from The Simpsons to Doctor Whoand beyond.

In his 2002 article “Six Degrees of St. Elsewhere”, McDuffie's original argument was that comics were the only mediums to take intertwining continuities so seriously, because otherwise the finale of St. Elsewhere would have flippantly connected every bit of television ever made.

With more and more studios announcing plans to turn their assorted properties into interconnected cinematic universes, perhaps we're not too far off being able to chart a similar universe for movies. Could we actually be headed for a movie market where every major tentpole could be placed in a hypothetical snow globe?

We doubt that many Hollywood executives have heard of the Tommy Westphall Universe hypothesis, or the recent glut of theories that connect every Pixar movie in the same magical realm. But money talks, and thus the loudest argument for stronger links between otherwise unconnected big screen properties has been Marvel Studios' own cinematic universe.

What is Marvel doing right?

Although Marvel Studios is the umbrella for the individual Iron Man, Thor, and Captain America franchises, every film they've made to date could be connected in one 10-part franchise. Even Guardians Of The Galaxy, the most remote instalment to date, has its space opera shenanigans tethered to the franchise through-line by the running story of the Infinity Gems, which also appeared in Captain America: The First Avenger, Avengers, and Thor: The Dark World.

Guardiansis also a key example of how Marvel has a vast well of intellectual property from which it can draw. At the start of all this, the Hulk was the best known character to movie audiences, but with the screen rights to their other big-hitters like Spider-Man and the X-Men tied up at other studios, they've quickly elevated second-tier characters like Iron Man, Thor, and Captain America to the same level, and used that success as a platform to salvage the likes of Star Lord, Rocket Raccoon, and Groot.

As Marvel adds to its ongoing franchise, their universe is getting bigger, not smaller. For the time being, it's still in an extended grace period at the box office - apparently, they can do no wrong. Aside from anything else, they've cracked a way to massively accelerate the turnaround time on sequels by using different actors and directors from one film to the next.

If there was an indicator that movie audiences would follow a story spanning several movies before this, it was the Harry Potter series. Only Harry Potter And The Sorcerer's Stone stands alone, and for all of the sequels, you either need to have seen the previous instalments or at least read the books, and yet it only got bigger over the course of eight movies in a decade.

Marvel has superseded that number in just six years. At this rate, by the time 2018 (the 10th anniversary of the first Iron Man) rolls around, they'll be on their 18th feature, widely speculated to be a third Avengers movie. That's assuming they continue to hold the audience's interest, but on the strength of Guardiansalone, a declining box-office doesn't seem likely to happen any time soon.

So what about other comic book franchises?

Marvel's success sometimes makes it seem like they have the only game in town, but we're starting to see their methods rub off on other studios with comic book properties. There's a storied rivalry between DC and Marvel Comics in which the latter definitely has the upper hand as far as cinema is concerned.

While Warner Bros' animation department turns out lots of direct-to-DVD movies based on the Justice League and its assorted members, a cinematic version has yet to manifest itself. Batman has been their biggest hitter since Christopher Nolan's hyper-real Dark Knight trilogy, which was never going to cross over into the territory of superhuman characters, and a long-gestating attempt to reboot Superman underwhelmed when it finally arrived under Bryan Singer's direction in 2006.

Things appear to be on track since last summer's Man Of Steel. Batman V Superman: Dawn Of Justice will be with us in March 2016, which is currently filming back to back with a Justice Leaguemovie, pencilled in for 2017. Solo movies featuring Wonder Woman and Aquaman and a spin-off team-up with Green Lantern and the Flash should also abound in the next few years - Warners has booked in release dates from here to 2020.

Their approach still seems a little ass-backwards though. While we can understand the desire to avoid aping Marvel's approach of building franchises expressly to build towards the team-up event, it didn't hurt the character development. Plus, it's still baffling to us that nobody has figured out how to put Wonder Woman on screen, particularly given the quality of the excellent DC Animated Universe movie that went straight to DVD in 2009.

Moreover, all indications are that Warner's Shazammovie, which recently cast Dwayne Johnson as the villainous Black Adam, won't be in continuity with these other movies. This could just mean that there are no transparent links, but if they're actively precluding Captain Marvel (or whatever they call him to avoid confusion with Marvel's namesake character) from meeting Superman et al, it's a puzzling move.

We're seeing something similar in their TV approach too. The Flashwill spin off from Arrowthis season, but other DC Comics shows like Constantineand Gothamwill be self-contained, and apparently we won't see Stephen Amell or Grant Gustin joining Henry Cavill and Ben Affleck on the big screen either.

Marvel is only just now finding its feet with Agents Of SHIELD, but DC's movie plans thus far seem to have stalled as a result of an unwillingness to put all of its eggs in one basket, as if they'd sooner diversify their properties than let them all play together.

Fox seems more pragmatic, with X-Men and Fantastic Four screenwriter Simon Kinberg refusing to rule out a crossover in the future. With no obligation to cross those properties, they don't have to commit to that sort of thing, but they seem to be making an effort to keep it open as an option. Days Of Future Pastreset the bar at the level of the grounded, black leather-clad Bryan Singer movies, so that's in keeping with what little has been revealed about Josh Trank's new take on Marvel's first family.

Having gotten burnt on X-Men Origins: Wolverine, the studio is also back in the business of spin-offs based around specific characters, like Gambit (apparently off the back of Channing Tatum expressing a desire to play the mutant) and Deadpool, (at last scheduled for 2016, after a long period of development between star Ryan Reynolds and Zombieland writers Rhett Reese and Paul Wernick) alongside the main franchise.

All of which brings us to Sony, a studio which seems to be at the forefront of this recent bout of intertextual lunacy. Some time before the release of The Amazing Spider-Man 2in April, they touted a cinematic Spider-verse that would comprise two more Amazing Spider-Man movies and solo spin-offs featuring the Sinister Six and Venom.

But the widespread critical and financial disappointment of The Amazing Spider-Man 2 has led to something of a recalibration of their plans. The Amazing Spider-Man 3 swapped places with The Sinister Six in their schedule and they doubled down by announcing Untitled Female Superhero Spider-Man Movie for 2017. Untitled Female Superhero may well be your favorite female character in the Spider-verse, but personally, we're finding it tough to muster much enthusiasm with so little information on that one.

The most recent rumours suggested that they'd be going forward with a soft reboot of the franchise, making the Dirty Dozen-style Sinister Six movie with a new actor playing Spider-Man. Andrew Garfield is a Spider-Man who deserves better scripts than Sony has been giving him, so we'll just have to hope that their nutty plans to run their only big-hitting franchise into the ground don't dispense with the one good thing they've got going for them. The thing is, this isn't the only area where they're trying to ape the Marvel model.

What about non-comic book properties?

Sony has given us two big reasons for this article in the last few weeks, most recently their plans for a seven-movie Robin Hood cinematic universe. This week, they made a deal for Hood, from screenwriters Cory Goodman and Jeremy Lett, (the upcoming Lore) which will apparently kick off a franchise where the Merry Men could get solo movies in the future.

It's possible to make a good movie out of any idea (case in point: The Lego Movie) but can we all, right now, agree that nobody is interested in seeing a Will Scarlett movie? Or an Allan A Dale movie? Can we at least agree that there are few things you can say in seven Robin Hood movies that Ridley Scott didn't comprehensively evade over the course of his 2010 movie with Russell Crowe.

The other news story was, yet again, related to Ghostbusters. God forbid any more members of the original cast should pass away before a new movie happens, but we've already seen how death won't stop Dan Aykroyd from haunting the idea of a continuing Ghostbustersfranchise. His latest brainwave for the series was that there'd be an interweaving franchise with several different teams of Ghostbusters, an idea that smacked of Sony's current franchise-daft approach to Spider-Man and now Robin Hood.

But it's not only Sony and it's not only comics. Other studios are re-opening formerly closed avenues in order to establish their own cinematic universes. Universal Pictures is once again revisiting classic monsters from the public domain, following 2004's Hugh Jackman-starring monster mash, Van Helsing.

That film didn't lead off into a franchise (although we don't think that's what they were aiming for given the ending) but with Roberto Orci and Alex Kurtzman at the helm of a few monster movies on their slate, they've already retro-fitted their very literal Bat Man Begins origin tale Dracula Untold as the first instalment in a series of interconnected films, by shooting new scenes to top off their new take on Vlad the Impaler.

Next up is their 2016 reboot of The Mummy, directed by Kurtzman and scripted by Billy Ray (Captain Phillips) and Jon Spaihts (Prometheus), and it's fair to assume that new takes on the Wolf Man, the Invisible Man, and the Creature from the Black Lagoon could follow. Lionsgate's I Frankenstein and Fox's upcoming Victor Frankenstein definitely won't count towards it, so we'll most likely see another take on Frankenstein's monster too.

And of course, having done so well with Marvel's cinematic universe, Disney will soon be revisiting a cinematic galaxy far, far away, with the aim of producing one Star Wars film a year - either an episode in the continuing saga or a spin-off based around characters like Boba Fett and Yoda. While Marvel and the producers of X-Men have an endless line of characters, Disney has a line of writers and directors who grew up watching the films who can bring a new take to it, already headed up by JJ Abrams, Rian Johnson, Gareth Edwards and Josh Trank.

So why all the cinematic universes?

In conclusion, there are a few reasons why studios are so eagerly developing continuities after Marvel's model. The acceleration of sequels is a biggy - a studio like Sony has no current franchises to speak of, so a speedier production line may seem like an appealing way to mobilise their properties. That's not to say that audiences necessarily have the same level of interest in a Robin Hood or Ghostbustersmovie every single year, but they seem to be trying it out.

On another level, locking a series in for several instalments is one way to keep big stars interested in playing characters on the big screen. In any interview where a movie star is asked about television, they'll praise the writing and ponder about the opportunity to explore a character over a greater screen lifespan than a two hour movie can offer.

That's how stars like Kevin Spacey and Matthew McConaughey wound up boarding shows like House Of Cards and True Detective, respectively. But in the movies, you can lock in Robert Downey Jr and Samuel L Jackson for contracts of six pictures and more if you plan to use the character in lots of different movies. It's not like Nick Fury has been a more complex character than Frank Underwood, but you can see the appeal.

Plus, just look at the year that Scarlett Johansson's had, starring in such leftfield fare as Her, Under The Skin, and Lucybetween her more lucrative retained role as Black Widow. It wouldn't be hard to get cynical about how this proliferation and expansion of franchises will continue to crowd out original films, but big stars can still patronise more interesting projects if they have a popular continuing character to which they can return.

The success or failure of this model all comes back to Guardians Of The Galaxy, which really typifies how Marvel has done so well and also shows how they're going to keep going for the foreseeable future. They're not leaving drunk messages on Sony's answer phone asking for Spider-Man back, because they have a vast reservoir of intellectual property to be getting on with, and an audience who's eager to discover it.

It may be that some of these planned continuities never make it past being announced or that some will be roaring successes or that some will crash and burn. Over-saturation is a bridge that some studios will have to cross if they hope to replicate Marvel's unparalleled hit rate, but don't be too surprised if all these tentpoles connecting up eventually leads to every blockbuster being snow-globed.

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