Yesterday, we got the news where Benedict Wong suspected that Doctor Strange 2 would begin filming next year, but we didn't really get into any specifics. As it turns out, the movie could be starting production very early into 2020.
As per Discussing Film:
Though we know some of the movies that Marvel has been working on for Phase 4, we still have no idea what the slate of releases is. We know that Black Widow, The Eternals, Shang-Chi, and Doctor Strange 2 are in the works, but we don't know when Marvel plans to release each movie.
If Doctor Strange 2 has an early 2020 start though, we could be looking at a release sometime in 2021.
While nothing official has been released, rumor has it that the next adventure of Stephen Strange will focus on a trip to the Nightmare Dimension, and we'll be meeting new characters like Brother VooDoo and Clea. We don't know more than that, but it's likely we could also see some involvement from Mordo.
Personally, I'm hoping for a team-up with Scarlet Witch, since I'm interested to see how her powers factor into Marvel Mystic, but I guess I'd prefer they link her to the mutants first should they introduce the X-Men.
For now, the next Marvel Studios film set to come out is Spider-Man: Far from Home, and it's set for a release on July 2.
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