Spider-Man: Far From Home arrived a few months before the storm between Marvel and Sony broke out. The rights to the arachnid are currently still under Sony's control, but the new agreement allows both companies to develop their own universe with Peter Parker played by Tom Holland.
At the end of the film, Mysterio and Spider-Man had a fierce final battle that ended with the supposed death of the master of illusions, who was gravely injured by a stray bullet from his own drones.
However, his final trick was to send a video to TheDailyBugle.net, a news outlet led by J. Jonah Jameson (J.K. Simmons), where Mysterio blamed "Spider-Man" for all the terrorist attacks he had committed, claimed his own death, and also revealed his identity to the world: Spider-Man is Peter Parker.
While most fans began speculating about what would happen to Spider-Man now that his secret identity is known worldwide, some fans closely analyzed what Mysterio had recorded and compared it to other parts of the film.
Is it possible that this supervillain is still alive? The circumstances of his death have been very confusing, but apparently a fan named The_Art_Jedi posted a theory that could explain Mysterio's final deception and why he believes he is still alive.
Not sure if this has been discussed before, but Mysterio’s team specifically CGied his suit in for the news. Plus Mysterio never had time to record a video leaking Peter’s identity, he’d had to have done it after he faked his death! from r/marvelstudios
"Not sure if this has been discussed before, but Mysterio’s team specifically CGied his suit in for the news. Plus Mysterio never had time to record a video leaking Peter’s identity, he’d had to have done it after he faked his death!"
When ComicBook had the opportunity to talk to the producer of "Spider-Man: Far From Home", Amy Pascal, they asked her if Mysterio had survived. She simply responded with "You don't know".
Director Jon Watts commented on the possibility that Mysterio had survived: "It's Mysterio, but who knows? He definitely seemed dead". It wouldn't be the first time this villain made everyone believe something completely different from reality.
In addition to all this, producer Eric Carroll previously suggested that Mysterio would appear in future Marvel movies. The filmmakers wanted a relationship similar to Stephen Strange and Karl Mordo as seen in "Doctor Strange", but now everything is uncertain:
"We wanted to find something similar to what we did in 'Doctor Strange'. We wanted to give them time to have a relationship so that when we could do something different with Mysterio, it would feel like a real betrayal... and set the stage for something really spectacular. If we can do something more with this character, then we already have that very personal relationship he has with 'Spider-Man'," he commented.
Finally, Kevin Feige commented on how important it would be for the future of Spider-Man for his secret identity to be known. The sequel they have planned will go in a completely different direction than the previous two films, and the return of Mysterio has not been denied. Is he alive? Only these Marvel executives know.
