All New All Different Marvel

The new poster for the Marvel Universe puts Iron Man front and center. Credit: Marvel Entertainment.

Those who aren't into comics won't care that Marvel is in the midst of a big crossover event called Secret Wars. Why should they? The comics aren't usually material to Disney's (NYSE:DIS) business. Usually.

That changes this October, when Marvel resets its comic book universe with Iron Man as its lead character. Not Spider-Man. Not Captain America. Iron Man. And it's all Robert Downey Jr.'s fault.

In an interview at Marvel.com -- and in a corresponding press conference you can listen to at Word Balloon -- writer Brian Michael Bendis explained that Marvel is reorienting its universe to address Iron Man's movie-fueled fame. "He's probably the most well-known super hero in the world alongside Batman. That is an interesting thing," Bendis said. 

Why should investors care about any of this? If Robert Downey Jr. has remade Marvel to this degree -- and it appears that he has -- then his ultimate departure from the role could have financial consequences at Disney's studio division.

How Marvel has remade Disney's Studio Entertainment group
To better understand the impact, we need to look at how the division has changed since Disney completed its acquisition of Marvel Entertainment on Jan. 1, 2010. Both operating income and operating margin have soared as blockbusters such as Avengers and Iron Man 3 have earned big at the box office:

Disney Studio EntertainmentFY 2014FY 2013FY 2012FY 2011FY 2010FY 2009
Revenue $7,278.0 $5,979.0 $5,825.0 $6,351.0 $6,701.0 $6,136.0
Operating income $1,549.0 $661.0 $722.0 $618.0 $693.0 $175.0
Operating margin 21.28% 11.06% 12.39% 9.73% 10.34% 2.85%

Source: S&P Capital IQ, author's calculations. 

Marvel has also remade Disney's licensing business, and Iron Man has played a big role. The Licensing Letter ranked Avengers-themed merchandise as the third-best performer among major superhero brands in 2013, racking up $325 million in retail sales that year. Messing with the Avengers means messing with a proven moneymaker.

What to watch for now
We won't see the new Iron Man comic book until October. In the meatime, Ant-Man arrives in theaters next month, and production work continues on Captain America: Civil War, due next May, and co-starring Downey Jr. After that, he's apparently signed to appear in the second half of the Avengers: Infinity War two-parter (now scheduled for 2019). His days of donning the armor are limited. 

We've known that for a while, of course. "Phase 3" of the Marvel Cinematic Universe was always meant to be a bridge to a new set of Avengers. Paul Bettany's Vision helped kick-start the transition in Avengers: Age of Ultron. What's changed is that, even as the transition was underway, the comics universe remained distinct. No longer. Now what appears on screen impacts the rest of what we'll see in other media -- beginning with making Iron Man the signature character of the Marvel Comics Universe.

That's a strong, symbolic move that makes sense for now until 2019, when Downey Jr. takes his final bow. After that? Better get the casting team working on a replacement. Either that, or look for Marvel to elevate other characters to be the face of its movies.

Tom Holland could kick off the process when he takes his turn as Spider-Man in Civil War. Do you agree? Disagree? Leave a comment below to let me know what you think.

Tim Beyers isn't the hero Fooldom deserves, but the one it needs right now. He's also a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission and owned shares of Disney at the time of publication. Check out Tim's web home and portfolio holdings or connect with him on Google+Tumblr, or Twitter, where he goes by @milehighfool.

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