After all, the audience knows that none of the big name characters are going to die. Most of them are already announced to appear in next year's Captain America: Civil War, or subsequent movies down the line (Thor: Ragnarok, for example, if not Avengers: Infinity War). Along the same lines, the very existence of those movies means that there's never any possibility of Ultron's plan succeeding even a little bit. You can't annihilate the human race, because then Thanos would have no one to threaten in the next movie.

The shared universe aspect hurts Age of Ultron in other ways. The death of Quicksilver feels muted, because the last character who died in an Avengers movie got brought back to life for a TV show within months; why should we care about characters dying when we're in a world where they can literally just come back to life later?

It's not just Age of Ultron that is feeling the strain of sharing its toys: Agents of SHIELD has had to deal with the fact that Captain America: The Winter Soldier disbanded SHIELD before the end of its first year, although that decision was also undercut by the creation of the nameless Avengers organization run by former SHIELD boss Nick Fury at the end of Age of Ultron. For those keeping track of things, that means that SHIELD was replaced by no less than three SHIELD-esque organizations — two of which call themselves SHIELD, both of which in Agents of SHIELD — in the space of 18 months. Suddenly that big Winter Soldier finale feels a little less meaningful.

It definitely should; by rights, if all the information SHIELD had was released into the public domain as apparently happened in Winter Soldier, the Marvel world would have been significantly different in all of the future movies. However, it's a plot that's been dropped because there needs to be a status quo to work from in the other movies.

I'm reminded of a line often attributed to Stan Lee, when talking about what comic book fans look for in stories. Reportedly, as the common wisdom goes, he explained that fans don't want change; they want the illusion of change. It's an attitude that makes sense, as much as it seems dispiriting to hear. With the many moving parts of the Marvel comic book universe, in which multiple series are published simultaneously, many of them sharing concepts if not characters, there needs to be a default status quo to which characters return to allow the toys to be used by as many creators as necessary at any given point. The same, it seems, is starting to become true of the Marvel Cinematic Universe.

In a way, it was unavoidable; there are only so many stories you can tell in a shared universe before they start, if not contradicting, then at least overlapping each other. When you promote, as Marvel has, the interrelatedness of your stories ("It's all connected," as the tagline goes), that's a selling point, instead of a bug — until the existence of those other stories starts limiting what you can achieve with each individual movie or television series. The question then becomes, at what point does your audience realize that you're standing in place in terms of narrative momentum, and are you doing so in such an entertaining way that they don't care?

Comic books have been dealing with this problem for decades without really managing to solve it. Marvel eventually ignores previous stories where necessary, whereas DC chooses to reboot its universe every decade or so to allow for a relatively clean slate (Tellingly, the same is true of their respective movie universes; Warners is rebooting Batman yet again with next year's Batman v Superman: Dawn of Justice, building off of a reboot of its Superman franchise, while Whedon has admitted to essentially ignoring Agents of SHIELD when making Age of Ultron). Both, however, have seen their core audiences shrink over time as a result.

Is that, then, the future for superhero shared universes, or will someone, somewhere, manage to find out how to successfully manage an interconnected world in such a way that true change and forward motion can happen without pushing everything apart? The only thing that's certain at this point is, somewhere — whether at Marvel, Warner Bros, Sony or Fox — someone is trying to find the answer right now.

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