8 Actors We Wish Hadn’t Already Appeared In The MCU

There are plenty of actors who could take home the crown of King of the Nerds, and Nathan Fillion seems like a shoo-in for the role. His overt popularity came from his breakout performance in the ever loved sci-fi TV show Firefly. While he's never been a massive Hollywood star, he seemed perfect for the MCU, especially in the irreverent Guardians of the Galaxy.

Fans were eager to see what this beloved performer would be doing in the movie, but they actually didn't end up seeing him at all. In fact, even his voice wasn't recognisable thanks to the amount of vocal editing that went into it.

He appeared as the "Monstrous Inmate" who antagonised the crew before getting promptly put in his place by Groot. It was a blink, and you'll miss it cameo - which you could still miss without blinking - and this came as a disappointment to many fans who couldn't wait to see Fillion bring his roguish charm to the MCU.

To make matters worse, he was even scheduled to make a cameo as Simon Williams, AKA Wonder Man, in Guardians Vol. 2, but this ended up being cut from the film. There's still hope this character might make it to the screen for Phase Four, but for now, fans will at least get to hear him voicing the role in Marvel's M.O.D.O.K.