The following post contains SPOILERS for WandaVision Episode 5.

So far, WandaVision has been one wild ride. At the tail end of Episode 5, we’re hit with a shocking surprise cameo from Wanda’s brother Pietro AKA Quicksilver. What makes this appearance so uncanny is that Pietro isn't portrayed by his MCU actor Aaron Taylor-Johnson, but his X-Men counterpart Evan Peters. But why?

As Darcy (Kat Dennings) puts it, it's a “recast” in the squeaky clean suburbia of Wanda's imaginings. Speaking with, showrunner Jac Schaeffer explained the thought process behind bringing Quicksilver — who previously perished in Avengers: Age of Ultron — to the Disney+ show. “We were like, how in the world are we going to make this make logical sense?” Schaeffer said. “Because that's the thing, you can hatch a million great ideas, but to make them land, to make them be grounded, to make them feel organic to the larger story.”

In order to make the cameo feel natural, Schaeffer and his team turned to ’80s sitcoms like Growing Pains and Full House, which served as inspiration for WandaVision. “We had long had the idea of the trope of the brother, or the relative, or whoever comes to town and like, stirs things up with the family — that sitcom trope,” Schaeffer explained.

The implications for Peters’ inclusion in the show are huge. Many fans have theorized that since Taylor-Johnson’s Pietro is dead in this timeline, Wanda’s subconscious has plucked him from another reality — like Fox’s X-Men universe. Marvel has been teasing its multiverse concept for a while now, and this could be the very beginnings of it.

“This show is such a mind scramble, and because it’s working on so many levels, and there’s so many notions of what’s real and what’s not, and performance, and casting, and audience, and fandom, and all of that,” Schaeffer continued. “We just thought it would be the biggest thrill to bring Evan over to the Marvel Cinematic Universe.”

New episodes of WandaVision debut every Friday on Disney+ through March 5.

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