Is Wonder Man finally going to make an appearance in a Marvel movie? It sure looks that way, as new Guardians of the Galaxy Vol. 2 set photos reveal Nathan Fillion is playing this iconic comic book character, otherwise known as Simon Williams. This is actually the second character Nathan Fillion has played in this particular sci-fi franchise.

In the first Guardians of the Galaxy movie released in 2014, Fillion voiced a big blue alien creature in the prison scene, which finds Groot and Rocket Raccoon teaching him a lesson. In the sequel, he gets to take on a much more substantial role. He is Simon Williams, a former Masters of Evil member and brother of the Grim Reaper. In the comics, Williams becomes reformed and eventually joins The Avengers.

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So, what's with all the movie posters featuring Simon Williams in the leaked set photos courtesy of At one point, Simon decided to quit the Avengers and become an actor. He was later pulled back into the Avengers as an active member, though he's known as one of Marvel's few pacifists. He is also a member of the Avengers Unity Division. But the character eventually paid the ultimate price when going up against the dastardly Apocalypse Twins in a move to defend Earth.

Nathan Fillion is featured on a number of movie posters starring Simon Williams. It appears that a theater in Guardians 2 will be running a Simon Williams Film Festival. The photos were snapped outside a real theater in Cartersville, Georgia. Willaims apparently played in many different genres. He stars in the romantic comedy Oh, Rebecca, the Conan-inspired Arkon, which is based on a Marvel comics character, a fantasy thriller sequel revolving aournd a male witch called Haxan 2, and a Steve Jobs-inspire biopic about Tony Stark, which we don't get to see pictures of here.

Not only do these set photos tease Nathan Fillion as the once and future Wonder Man, they seem to confirm that some of Guardians of the Galaxy Vol. 2 will take place on Earth. What isn't known is whether or not these are part of a Peter Quill flashback set in the 80s, or if this is present day. Some of the posters look dated in style, but a Tony Stark biopic hints that this is at least set sometime in the late 2000s.

Many fans are speculating these posters and this film festival are just a fun Easter egg. And that we won't actually see Nathan Fillion suit up as Wonder Man. Nathan Fillion had a similar superhero cameo in director James Gunn's R-rated comedy Super, where the Castle and Firefly star played TV superhero the Holy Avenger. We haven't heard anything about Wonder Man appearing in a Marvel movie, but he could be one of the 67 characters showing up in Infinity War. Is there any change Simon Williams will join the on-screen Avengers? We'll have to wait and see.