There are big SPOILERs ahead, so be aware. Halfway through WandaVision slowly unfolding its story with each new episode, the entire MCU fandom was suddenly and completely sidetracked by a throwaway line from Monica Rambeau, when she mentioned knowing "an aerospace engineer who'd be up for this challenge," of building a fallout shelter designed to get her inside the magical "Hex" surrounding the town of Westview.

The line immediately sparked a flurry of fan theories, with audiences being convinced Monica was referring to Reed Richards aka Mr. Fantastic, the leader of the Fantastic Four, who would soon be making his MCU debut on WandaVision. Unfortunately, that did not happen. In a new interview, Matt Shakman, the director of the show, admitted Reed's appearance was never on the cards at all.

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"Some of those Easter eggs are absolutely intentional. And then some things, like just trying to clarify what was Monica's plan with regards to the Hex [were not]. We did reshoot a little thing there, changed some dialogue, added the aerospace engineer which was never an intention on our side to set up the Fantastic Four (laughs)."

Fans can be forgiven for thinking WandaVision might try to sneak in a major character introduction, since the same thing had happened with Spider-Man and Black Panther in Captain America: Civil War, and Captain Marvel in Avengers: Infinity War.

Monica's engineer friend turned out to be a new character named Major Goodner, who seems like a perfectly nice person, but in the eyes of fans, suffers from a major character flaw of not being Reed Richards, or Professor X, or Magneto, or any of the dozen other major characters from Marvel Comics that fans were hoping would turn out be the secret cameo that had long been teased by the cast and crew of WandaVision. According to Shakman, it was difficult watching the carefully constructed narrative of the show be completely sidetracked by wild fan theories with no basis in reality.

"[Fan theories are] charming and wonderful. But we're building to this rover set piece, which I have worked my butt off on for well over a year creating this rover. And all of a sudden, everybody wants to know who's going to meet her there, and I know it's going to be this wonderful actress who's playing Major Goodner, and it's not going to be Reed Richards... I want people to be invested in what is the origin story of a different character that Monica Rambeau is becoming, and instead, we're being distracted by someone else. So yeah, the director-producer in me is like, 'Oh, don't run with that one!' Because I didn't want the focus to shift from what was important, which is the story of Monica traveling through that Hex."

Written by Jac Schaeffer and directed by Matt Shakman, WandaVision stars Elizabeth Olsen as Wanda Maximoff/Scarlet Witch, Paul Bettany as Vision, Randall Park as Agent Jimmy Woo, Kat Dennings as Darcy Lewis, Teyonah Parris as Monica Rambeau, and Kathryn Hahn as Agnes.