One of the biggest surprises in the Disney+ Marvel show WandaVision was the appearance of Evan Peters as Wanda’s brother Pietro. Showrunner Jac Schaeffer has spoken more about this, and revealed there was no back-up plan if Peters couldn’t do it.

Peters played Pietro–aka Quicksilver–in the X-Men films, with Aaron Taylor-Johnson appearing as Pietro in the Marvel Cinematic Universe. While the movie rights to the X-Men are now owned by Disney, the two superhero universes are yet to cross. The final episode of WandaVision reveals that it’s not Pietro at all, but an ordinary man named Ralph Bohner that Wanda has “recast” as her dead brother, making Peters’ appearance little more than an in-joke. Nevertheless, Schaeffer states that she was only given permission to use Peters at the last minute.

“[Using Peters] was an enormous question mark for a very long time,” she told the New York Times. “And it took a while to figure out if it would be possible. It was late that it was finally confirmed that we could do it. But we were writing for it. Evan is such a chameleon in that way, that could play an amalgamation of [Full House’]s Uncle Jesse, [Family Ties’] Nick, and Joey from Friends. He could play those layers.”

Schaeffer admitted that if the bosses at Marvel had said no to using actors from the X-Men universe, then she didn’t have an alternative. “The ground is often shifting, and sometimes that’s how the amazing things occur,” she said. “There are a couple of scenes that I wrote that I’m like, “This is genius!” And then it was like, “No, you can’t have that toy.” You find a different toy that suits your show better. But there wasn’t a Plan B on that. There were just very, very intense hopes and dreams, and they were met.”

It’s worth noting however that Schaeffer’s comments do seem to contradict those made by Marvel Studios head Kevin Feige last month. In an interview during the TCA winter press tour, Feige suggested that the decision to cast Peters was made early on in WandaVision’s development. He said, “There were all sorts of discussions, but I believe it, we ended up going with what you saw relatively early on in the development process. And just another way that certain people were messing around with Wanda.”

WandaVision’s final episode hit Disney+ last week–check out GameSpot’s breakdown of the episode here. The next Marvel show will be Falcon and the Winter Soldier, which releases later this month. Check out the latest posters for the show.

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