WandaVision showrunner Jac Schaeffer says some Marvel Cinematic Universe characters were off-limits to include in the show. Phase 4 of the MCU will introduce several new characters, but it will also elevate the roles of others who have been around for a while. Wanda Maximoff aka Scarlet Witch (Elizabeth Olsen) and Vision (Paul Bettany) have been part of the MCU since Phase 2, but WandaVision is the first time that they are at the forefront of a story.

With only four episodes released to this point, WandaVision has already proven to be unlike anything the MCU has done before. The show's fake/altered reality featuring the witch and android couple living together in a sitcom-styled suburb is extremely different. And while WandaVision has focused on Scarlet Witch and Vision, the show also includes several other characters with MCU histories. Darcy Lewis (Kat Dennings), Jimmy Woo (Randall Park), and Monica Rambeau (Teyonah Parris) have all returned already. The use of other MCU characters furthers WandaVision's connection to the rest of the shared universe, but that doesn't mean any character could've appeared.

Related: WandaVision Episode 4 Cast Guide: Every New & Returning MCU Character

In a new interview with Digital Spy, showrunner Jac Schaeffer was asked about the creative process of making WandaVision. Schaeffer got her start with the MCU doing Captain Marvel rewrites and then was hired to write Black Widow. While discussing the development of WandaVision, she was asked if Marvel gave her full control over which characters to include. Schaeffer said she was given a large list of characters that were available to use.

It's not free rein. [Marvel has its] ideas and larger interconnecting pieces. So, there were characters that were suggested to me – a larger list of characters. With Randall Park and Kat Dennings, I was like: that's an excuse to work with two people I admire so, so, so much. And also, I saw a very clear way for them to fit in.

Teyonah Parris and Randall Park investigate outside of Westview in WandaVision

Having complete free rein over which characters could appear in WandaVision or any MCU property is practically impossible at this point. The MCU currently has 25 movies and TV shows in various stages of development. In many cases, the movies and shows build off one another to help create the larger MCU story. That is the best explanation for why Marvel puts some limits over which characters can and cannot be used on a given project. And with several of these projects having overlapping production schedules, there is also the real-world logistics of an actor being available that could limit what characters are viable options.

The good news for WandaVision viewers is that Schaeffer is thrilled with the cast she got at the end of the day. The show has already featured five characters from previous MCU properties, but there are still multiple episodes to go. There is no shortage of speculation that other familiar characters like Ultron, Quicksilver, and Doctor Strange will appear before WandaVision ends. Plus, there are many theories about other Marvel characters from the comics who could make their debuts, such as Mephisto, Nightmare, and Wonder Man. So even if Schaeffer was somewhat limited in the list of characters at her disposal, it doesn't appear that WandaVision will be short on Marvel favorites.

MORE: WandaVision: Who Is Westview's Witness Protection Character?

Source: Digital Spy

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