It took a while — the wait seemed even longer, considering that his name was left conspicuously unmentioned during Disney’s Investor Day mega-event last December — but with just a simple tweet, Marvel Studios finally confirmed what fans had long known: that Oscar Isaac has been cast as Marc Spector, a.k.a. Moon Knight, in the upcoming Disney+ series and presumably beyond. (You don’t cast Oscar Isaac to play a superhero if you don’t have big plans for the character... unless of course you’re X-Men or Star Wars.)

That tweet, however simple a casting announcement it may appear to be, gave fans of the complex character something else to be excited about. Its brief message not only establishes the tone of both Moon Knight the character and the series bearing his name, but for the considerably darker themes and motifs currently making their way into the Marvel Cinematic Universe.

This shift towards more adult concepts could already be seen in earlier films like Black Panther, but has been kicked into high gear this year. WandaVision, for example, was at its core a story about a woman struggling to cope with immense grief, albeit a woman who just so happens to have otherworldly magical abilities. Wanda’s storyline is already confirmed to continue in March 2022’s Doctor Strange in the Multiverse of Madness, which tasked famed Evil Dead and Spider-Man filmmaker Sam Raimi with making the first “horror” movie in the MCU’s nearly 15-year history. Meanwhile, The Falcon and the Winter Soldier explored systemic racism and oppression.

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Then, of course, there’s two-time Academy Award winner Mahershala Ali’s Blade on the horizon. Blade is a vampire who hunts vampires, brushing up against demonic elements that make the character inherently darker, both thematically and cinematically, than any hero to exist in the Marvel Cinematic Universe thus far. (You have to imagine that Blade will literally be a dark movie, like Tim Burton’s Batman or the previous Blade films starring Wesley Snipes, if for no other reason than the character does most of his work at night.)

blade-trinity-wesley-snipes looking upset and confused
Image via New Line Cinema

As for how Isaac’s Moon Knight will fit into this more mature period of the MCU, look no further than the very first word of the tweet’s one-sentence message: “We are Moon Knight.” In the comics, Marc Spector/Moon Knight is a former U.S. Marine turned C.I.A. agent who suffers from multiple personality disorder. As a result, he’s adopted a handful of personas for the purpose of fighting crime, such as entrepreneur Steven Grant and cab driver Jake Lockley.

Multiple personality disorder (otherwise known as dissociative identity disorder) and mental health in general is quite obviously nothing to be treated lightly, which means it goes without saying that Moon Knight should take the topic seriously and handle the subject matter delicately. In the same way that Black Panther was a landmark for Black representation in superhero films, and Shang-Chi and the Legend of the Ten Rings looks like it will be a similar milestone for the Asian community, the embrace and exploration of Marc Spector’s mental health could also stand as a poignant moment of representation for those who find themselves fighting similar battles.

The MCU, as led by mastermind Kevin Feige, already deserves immeasurable credit for pulling off the impossible and creating an interconnected universe of movies and television. The MCU has also managed to grow increasingly mature while still appealing to a massive mainstream audience. Marvel’s current slate of upcoming projects, as well as the limited series we’ve already seen this year, suggest that the MCU isn’t afraid to continue carving out a more serious corner in the sprawling comic book universe.

Of course, how well these upcoming Marvel projects handle their more mature subject matter is yet to be seen. But given what we’ve seen from the franchise so far, the MCU seems to be ready to evolve alongside the audience it's been entertaining for over a decade now. We’re far older, and the world is far different, than it was back in 2008 when Iron Man first premiered. We’ve grown. By delving into themes such as grief, fear, and mental illness, the MCU is perhaps proving it's ready to grow with us.

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