Marvel’s next sequel — after new series Black WidowEternals, and Shang-Chi and the Legend of the Ten Rings — is expected to be Doctor Strange in the Multiverse of Madness, continuing from the first Doctor Strange film from 2016. Benedict Cumberbatch was expected to return as Doctor Strange, and Scott Derrickson, who helmed the first Strange, was supposed to come back as well.

Until tonight.

That’s when Derrickson tweeted that he and Marvel had “mutually agreed to part ways on Doctor Strange: In the Multiverse of Madness.” Derrickson blamed “creative differences” on his departure, thanking the company for “our collaboration” and announcing he would remain involved in the film as executive producer.

That immediately throws the film into a bit of uncertainty. Without a replacement director found soon, the movie may have a hard time hitting its announced May 7, 2021 release date. Even with a director, the movie needs to move into production pretty soon in order to be finished in time for that release date. And if Doctor Strange 2 isn’t ready by then, what, if anything, replaces it on Marvel’s release calendar? And how does all this affect WandaVision, the Disney+ TV series which stars Elizabeth Olsen’s Wanda Maximoff, who is also supposed to appear in Doctor Strange 2? Suddenly a lot of MCU Phase Four looks like it’s up in the air, and not in a cool spell of levitation kind of way.

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