When Zendaya was cast in Spider-Man: Homecoming, speculation ran rampant that she'd be playing Peter Parker's longtime love interest, Mary Jane Watson. However, the movie's producers decided that Zendaya would play a new character, named Michelle, who was definitely not Mary Jane. Zendaya herself even denied it! Of course, at the end of the movie, we find out that Michelle's friends call her "MJ," and the circle is now complete. Zendaya is MJ … but not Mary Jane? Okay.
Anyway, the nonsense reveal of Michelle's true identity points to the coming importance for MJ in Peter Parker's life. As fans of both the comics and the movies know, Peter and MJ's stories have been intertwined for years. She's first mentioned way, way back in 1964's Amazing Spider-Man #15, and fans (and Peter) finally got a look at her face in Amazing Spider-Man #42 in 1966. As the years went on, MJ became Peter's on-again, off-again girlfriend. In the '80s, she took their relationship to the next level when she revealed that she'd figured out his secret identity in Amazing Spider-Man #257. There were more than a few hints in Homecoming that seemed to indicate MJ has feelings for Peter — and might even know his secret.
Eventually, Peter and Mary Jane married in 1987's Amazing Spider-Man Annual #21. Twenty years later, in the critically divisive One More Day storyline, Peter literally sold his marriage to Mary Jane to the devil to keep his old, decrepit Aunt May from croaking after she was shot by bad guys.
Needless to say, this new movie MJ has a lot of weird times to look forward to.