We can, and no doubt will, debate which film was the proverbial canary in the coalmine, but there's little arguing that 2017 marked the beginning of the end of the cinematic universe -- or at least the often ill-conceived plans by rival studios to replicate Marvel's blockbuster success. It was as if Hollywood suffered its own Crisis on Infinite Earths, in which one shared universe after another collapsed upon itself, until only the Marvel Cinematic Universe stood on solid ground.

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The appeal of such shared worlds to studio executives is obvious, as they help to feed the same commercial hunger for the familiar that's sated by sequels and remakes. When done "properly," as in the case of Marvel Studios, a cinematic universe develops into a brand strong enough to provide tent-pole after tent-pole, and weather the occasional modest-performing release with no ill effects.

But a poorly conceived cinematic universe -- one whose reach far exceeds its fumbling grasp -- can result in disaster, sometimes a slow-motion train crash, and other times a quick, shocking explosion. This year we experienced a bit of both, as studios learned Marvel made creating a cinematic universe look easier than it actually is.

DC Extended Universe

justice league film

Warner Bros.' so-called DC Extended Universe stumbled out of the gate, with director Zack Snyder's divisive Batman v Superman: Dawn of Justice (or maybe it was with his divisive Man of Steel), and it never really regained its footing. However, it's not the poor critical and commercial performance of Justice League that may have doomed this shared cinematic universe, but rather the success of Wonder Woman.

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Set primarily during World War I, director Patty Jenkins' acclaimed film wasn't moored to the continuity established by its predecessors -- in fact, it retconned a troublesome detail from Batman v Superman -- and it didn't need to shoehorn in a cameo from the likes of Ben Affleck's Dark Knight or Ezra Miller's Barry Allen. Wonder Woman could to tell its own story, and develop Gal Gadot's heroine, free of the constraints of the studio's multiyear franchise plans. It's a lesson DC Entertainment learned quickly, with President Diane Nelson explaining earlier this year, “Our intention, certainly, moving forward is using the continuity to help make sure nothing is diverging in a way that doesn’t make sense, but there’s no insistence upon an overall story line or interconnectivity in that universe.”

Add to that talk of an emerging separate banner for DC Comics-based films, including a 1980s-set Joker origin, and remarks by The Batman Matt Reeves that his project "wouldn’t be filled with cameos servicing other stories," and what was presented in late 2014 as a "cinematic universe" begins to look more like a loose assembly of superhero features.

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Dark Universe

the mummy

Universal Pictures' long-gestating dream of a shared universe featuring updated versions of its iconic monsters may have seemed like a good, even logical, idea; after all, the original Universal Monsters films boasted recurring actors and characters. But when the Dark Universe finally launched in June with The Mummy, starring blockbuster machine Tom Cruise, those plans quickly imploded ... spectacularly.

The finger-pointing was immediate, with much of the blame for The Mummy's failure laid at the feet of Cruise, whose contract granted him broad creative control. But no matter who was at fault, the results were the same, with The Mummy delivering a projected $95 million loss for Universal, and seemingly unraveling the Dark Universe. By November, its chief architects, Alex Kurtzman and Chris Morgan, had left Universal, and the studio is now reportedly considering approaching producers and directors with monster films that would effectively stand alone, and share no continuity. Meanwhile, director Bill Condon's planned remake of Bride of Frankenstein, originally set for release in 2019, has been postponed but is said to remain in development.

Fox's X-Men 'Universe'

fox x-men movies

Never really a shared cinematic universe in the true sense, Fox's X-Men franchise has always been a relatively straightforward film series, with prequels, a handful of Wolverine spinoffs, and the semi-related Deadpool, which doesn't exist in the same continuity. The latter can also be said for the property's expansion into live-action television in 2017 with Legion and The Gifted, which share some characters but not necessarily the same timeline.

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That growth will continue in 2018 with X-Men: Dark Phoenix, Deadpool 2, and The New Mutants, which trades superhero adventure for horror tropes and Charles Xavier's school for a secret facility (how connected it might be to the rest of the franchise remains to be seen). The long-promised Gambit and X-Force movies are also in the pipeline, bringing with them the potential for an actual "universe." However -- and it's a sizable however -- the recently announced purchase by Disney of 21st Century Fox's key assets raises countless questions, including how the X-Men film rights will be integrated into Marvel Studios' larger plans. This time next year, or however long it takes for federal regulators to approve the deal, will spinoffs like Gambit or X-Force still be in the cards?

Sony's Spider-Man 'Universe'

Tom Holland in Spider-Man Homecoming

Nothing illustrates the fragility of the concept better than Sony Pictures' ambitions for a Spider-Man "universe," which now theoretically exists without the wall-crawler himself. There's an inescapable irony in the very co-production agreement that enabled Tom Holland's Peter Parker to be introduced into the Marvel Cinematic Universe and the Spider-Man series to be successfully rebooted (again) hinders Sony's own plans for the ancillary characters.

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You see, Holland's web-slinger won't appear in Venom, filming now with Tom Hardy, or in the planned Silver & Black (featuring Silver Sable and Black Cat), or, presumably, in Kraven, Mysterio or Morbius, which have also been mentioned. They're Spider-Man spinoffs only in the loosest sense, in that all of these characters are part of the larger film license. Still, that doesn't prevent fans or news outlets from repeatedly pressing producers about how, or whether, those projects relate to the world depicted in Spider-Man: Homecoming. The short answer is, they don't, at least for the time being; however, the longer answer can get a bit ... comical.

Transformers

Optimus Prime in Transformers The Last Knight

The reception for Transformers: The Last Knight wasn't what Paramount Pictures and Hasbro envisioned when they announced plans in 2015 to convert the blockbuster action franchise into an "expanded universe," Characterized by director Michael Bay as both "a final chapter and a new beginning," the fifth film in the series was intended to lay the foundation for this ambitious new universe. Bay himself boasted there are 14 Transformers stories already in development, although only a 2018 Bumblebee spinoff and an untitled sequel have been announced.

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It's not yet known how The Last Knight's disappointing performance might affect those ambitions: Although Transformers has never been loved by critics, it rolled out in June as the worst-reviewed of the franchise's five films; its $605 million global box office is also the lowest. Bumblebee: The Movie, a 1980s-set prequel featuring the fan-favorite Autobot, is scheduled for release on Dec. 21, 2018, but how many more of those 14 stories -- which presumably include the rumored Autobots vs. Decepticons origin film -- will eventually reach theaters is a question that looms as large as Cyberton over the franchise.

Hasbro Universe

hasbro universe

Announced in 2015, the planned Hasbro Universe evokes childhood memories of upending the toy box and pitting action figures from one property against those of another. In this case, however, it's Hasbro and Paramount Pictures mixing and matching toy franchises (G.I. Joe, Micronauts, Visionaries, M.A.S.K. and ROM) in what's envisioned as an interconnected movie universe.

Even if it's almost impossible to imagine what form such a universe might take, it's difficult to deny the concept's underlying genius: It strikes a chord of nostalgia among viewers of a certain age while making use of four lesser toy brands from the 1970s and '80s by pairing them with the more widely recognized G.I. Joe. Paramount staked out release dates last week for G.I. Joe (March 27, 2020), Micronauts (Oct. 16, 2020) and an untitled Paramount/Hasbro event film (Oct. 1, 2021), which certainly suggests that development of a Hasbro Universe continues apace. However, a lot can happen between now and 2020.