Marvel's untitled Spider-Man 3 is shaping up to be a huge film. Already, it's confirmed Jamie Foxx will reprise his role as Electro, which he first played in 2014's The Amazing Spider-Man 2. Fans immediately took that as a possible hint that the upcoming film will delve into the Marvel Multiverse. This seems more likely now that Benedict Cumberbatch is slated to return as Doctor Strange in Spider-Man 3.
The Sorcerer Supreme will fill a mentor role for Peter Parker, taking the place of Tony Stark and Nick Fury in Homecoming and Far From Home, respectively. This is big news for the film, and the MCU in general. More importantly, it cements the importance of Doctor Strange going forward. In fact, given everything known so far of the MCU's Phase 4, it seems apparent that Doctor Strange is set to become the new Nick Fury.
In the early days of the MCU, Nick Fury was the primary glue that connected the Phase 1 movies together. He appeared in the first two Iron Man films, in Captain America: The First Avenger and in the end-credits scene of Thor. This made it clear that all the movies took place in the same shared universe, and it also ramped up the lead to Marvel's first ensemble film, 2012's The Avengers.
Fury is of course still a major player in the MCU, but it now looks as if Doctor Strange will serve as the connective tissue between several Phase 4 projects. After all, the character is set to appear in his own film, Doctor Strange in the Multiverse of Madness, which will see the Sorcerer Supreme team-up with Wanda Maximoff.
The circumstances of Strange and Scarlet Witch's interaction hasn't been revealed yet, but she will be playing a major role in the film, which is supposedly in response to events in WandaVision, the MCU's first television series. Therefore, Doctor Strange already has some connection to the first entry in Phase 4, even if he isn't in it.
What's more, Doctor Strange's sequel somehow ties in with Loki, another upcoming Disney+ television series. The series will follow the alternate version of Loki who escaped from his own timeline in Avengers: Endgame, and it will see the debut of the Time Variance Authority. This seems to indicate Loki will be up to no good across time itself. With more alternate realities and time travel involved, it's likely Doctor Strange will have a connection to the television series, either directly or indirectly.
Plus, audiences now know the Sorcerer Supreme will play a major role in Spider-Man 3, a film that may also explore the Marvel Multiverse. It's clear Phase 4 will be dealing with all manner of alternate realities, which means Doctor Strange is now one of the most important characters in the MCU, like Nick Fury was.
Starring Tom Holland and Zendaya, the third MCU Spider-Man film is set for release on Dec. 17, 2021. An official title for Spider-Man 3 has not yet been announced.