Doctor Strange saw the future 14 million times in Avengers: Infinity War, so we're pretty sure he must have known he's set to star in another solo movie as part of the Marvel Cinematic Universe's Phase Four of films. The movie--Doctor Strange 2: In The Multiverse of Madness--is set to release on May 7, 2021.
Marvel Studios' president Kevin Feige officially confirmed the film on stage at the Marvel panel at San Diego Comic Con 2019, referencing the last MCU film Spider-Man: Far From Home by stating: "Just because (Quentin) Beck made up lies about the multiverse doesn't mean it isn't real."
Director Scott Derrickson is back at the helm for the Doctor Strange sequel, and while on stage at Comic-Con, he said the new film would lean more into the horror genre. "What excites me about Doctor Strange is from the comics--he doesn't fight villains from this Earth, he fights everything from everywhere. If I was gonna do a sequel we're gonna dip into the gothic and the horror -- we're gonna make the first scary MCU film," he said.
Doctor Strange himself--actor Benedict Cumberbatch--was also in attendance, and was serenaded by the crowd singing Happy Birthday when he first appeared on stage (apparently it was his birthday the previous day). "We're going to do some of the things we had in the first film with that twist of horror. He'll be facing unexpected things--he won't know what's coming at him. We're going back to trying to destroy him a bit," he said.
And in perhaps one of the most exciting news for Doctor Strange 2, it was confirmed the Scarlet Witch herself--Wanda Maximoff (as played by Elizabeth Olsen)--will also be in the film. Kevin Feige confirmed the events in the upcoming Disney+ show WandaVision will directly link to Doctor Strange 2.