It was revealed last year that Jamie Foxx will be reprising the role of Electro in the forthcoming film, which is officially titled Spider-Man: No Way Home.
This caused some confusion considering he last played the villain in 2014's The Amazing Spider-Man 2 back when Andrew Garfield played the web-slinger.
It was the last Spider-Man film before the character officially joined the Marvel Cinematic Universe withTom Holland in the role.
Alfred Molina has also been announced to return as Doctor Octopus having played the villain in Sam Raimi’s Spider-Man 2, which saw Tobey Maguire play the superhero.
These casting announcements have since generated many theories across the fandom, with many assuming the returns have been made possible by the inclusion of the multiverse – different worlds featuring a whole host of characters, dead and alive.
Many are now questioning whether the MCU is lining up the arrival of the Sinister Six, a villainous group comprised of characters from the world of Spider-Man.
Sony, who owns film rights to these characters, was planning on releasing a Sinister Six film before deciding to give one of its members, Venom, a standalone film.
The first Venom was a worldwide hit and the sequel – again starring Tom Hardy in the title role – will be released in 2021.
Another Sinister Six member is Mysterio, the antagonist played by Jake Gyllenhaal in Spider-Man: Far From Home (2019).
A further Spider-Man character to have been given their own film is Morbius.
Interestingly, when the trailer for Morbius was released, Marvel fans were shocked to see that it featured Vulture, the villain played by Michael Keaton in Holland's first Spider-Man film.
With Sony intent on making it very clear that these films are set in the same world as the MCU, could the studios be lining up the arrival of the Sinister Six in a future Marvel film?
“Guys, the MCU will soon have Vulture, Mysterio, and now Electro. Are they building the classic sinister six team? They’ve got half now, we might actually be getting the classic sinister six!” one excited fan wrote.
Morbius, starring Jared Leto, will be released next year after being delayed due to the pandemic.
Other characters featured in the supervillain group include Sandman and Kraven the Hunter.
With JK Simmons' Daily Bugle editor J Jonah Jameson showing up at the end of Far From Home, having only previously appeared in Raimi's trilogy, it certainly seems as if anyone to have appeared in any Spider-Man film in the past could show up in the MCU.
This was perhaps made more possible by the fact that Raimi was brought in to direct Doctor Strange in the Multiverse of Madness when Scott Derrickson stepped down.
Another Sinister Six member, Scorpion, is also expected to show up in the next Spider-Man film, which will be released this December.