Once a superhero franchise goes multiverse, it’s hard to go back.
No work of fiction ever needs permission to break the rules or push the boundaries of traditional storytelling, but the multiverse, at least as it’s been served up in recent Marvel movies, practically demands it. And for the moment that means a lot of cameo opportunities. “Spider-Man: No Way Home” opened the door to the concept, to mostly charming results, but now Benedict Cumberbatch’s master of the mystic arts is flying through the interdimensional portal with the concept in “Doctor Strange in the Multiverse of Madness.”
