Actor and Avenger Simon Williams/Wonder Man will be played by Aquaman's Yahya Abdul-Mateen II in the MCU, but because of Guardians of the Galaxy Vol. 2, audiences were convinced that Nathan Fillion would be starring in Wonder Man. A Nathan Fillion Wonder Man role has long been rumored online, and with the MCU using Disney+ to give characters who otherwise might not star in full-length solo movies a chance to shine, the Nathan Fillion Wonder Man fan casting became even more plausible. After using the streaming service to introduce lesser-known characters like Moon Knight and Ms. Marvel, the announcement of the upcoming Marvel Disney+ series Wonder Man signaled that Marvel Comics' Simon Williams was due the same treatment. Despite living in a post-John Krasinski Mr. Fantastic world, however, Marvel and Disney didn't opt for the Nathan Fillion Wonder Man fan cast. These longstanding MCU Wonder Man cast rumors weren't completely unfounded though.

The Nathan Fillion Wonder Man speculation stemmed from the fact that the former Firefly, Con Man, and Dr. Horrible's Sing-Along Blog star has consistently portrayed witty, handsome, and over-confident charmers — personality traits that make Marvel Comics Simon Williams, aka Wonder Man, so endearing to readers. This made Fillion perfect for playing a live-action MCU Wonder Man in the eyes of many. Moreover, while they've been but to bed by Aquaman and Watchmen star Yahya Abdul-Mateen II's Wonder Man role being confirmed, the rumors about Fillion taking on the role weren't unsubstantiated at all. In fact, Fillion was such a shoo-in for the role that he has actually already played Wonder Man in the MCU — sort of.

Related: Trevor Slattery's New Role Hints At Wonder Man's MCU Backstory

Nathan Fillion Has Already Played Wonder-Man

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MCU fans weren't the only ones to notice how suited Nathan Fillion is to the comic book portrayals of Simon Williams — Guardians of the Galaxy director (and recently crowned DC-Studios co-chair and CEO) James Gunn thought so too. Audiences thought that Nathan Fillion would become Wonder Man because he nearly appeared onscreen as the character. As a close friend of director James Gunn, Fillion participated in a Guardians of the Galaxy Vol. 2 cameo as Simon Williams. He even went on to voice Wonder Man in Hulu's MODOK show. However, Nathan Fillion's Wonder Man cameo in Guardians of the Galaxy Vol. 2 was ultimately cut from the movie. The cameo mainly consisted of Fillion appearing on a series of posters for the "Simon Williams Film Festival," which references the character's history of being a self-absorbed actor in the comics. Even though Fillion's cameo was not included, Gunn casting him as Wonder Man was done with the hope that he'd go on to play Wonder Man in a future MCU project. This would seemingly give him an inside track to starring in Wonder Man, making the dreams of many long-time Marvel readers/viewers come true. That being said, Yahya Abdul-Mateen II's Wonder Man is arguably a much better fit for the role at this point in the MCU.

Why Yahya Abdul-Mateen II Is A Better Wonder Man Choice

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Details on Wonder Man are still limited, but it is possible the upcoming MCU show will be more comedic in tone since Brooklyn Nine-Nine's Andrew Guest is the head writer. Nathan Fillion could pull off such a comedic Wonder Man take with ease — that's undebatable. The most likely reason Nathan Fillion isn't MCU Wonder Man, however, is his age. Fillion is currently 51 years old and is probably not looking to take on a major action-heavy superhero role that could keep him occupied for years. If the MCU Wonder Man's story lasts to tackle the West Coast Avengers or his Scarlet Witch romance, they'll need an actor who can play Simon Williams for many years to come. This is why Yahya Abdul-Mateen II's Wonder Man is much more suited for the future of the MCU.

While Nathan Fillion's Wonder Man would have been perfect for MCU Phase 1 or 2, the MCU wasn't ready to adapt Simon Williams then. Now, with more than 20 upcoming MCU movies and series slated for development and release, the MCU has begun adapting Marvel's more obscure characters, and Yahya Abdul-Mateen II is at the right place and time for the MCU's Wonder Man series. Although he isn't a long-established cult figure like Nathan Fillion, Abdul-Mateen II's roles in The Get Down, The Matrix Resurrections, and Aquaman show that he also has what it takes to bring Simon Williams to life.

For those who were looking forward to a Nathan Fillion Wonder Man debuting in the MCU, what's great about Abdul-Mateen II bagging the role is that it opens the doors for Fillion to play another MCU character. For the same reasons that would have made Fillion the perfect Wonder Man, he would undoubtedly do well as the MCU's Mister Sinister, Doctor Doom, Sentry, or even Beyonder. Considering how Fantastic Four, X-Men and Secret Wars are in the works, with the MCU continuously bringing on new actors to adapt more comic book characters, Nathan Fillion may still have a future in the MCU.

Next: MCU Phase 6 Has 8 Unannounced Movies & Shows: What We Think They Are

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