Spider-Man: Homecoming's upcoming, untitled sequel may feature some iteration of the Sinister Six, a classic group of Spidey's worst enemies. Recent casting reports have revealed that Jake Gyllenhaal is in talks to play Mysterio; additionally, Michael Keaton's Vulture, who is also a member of the Sinister Six, will return.

Fans have speculated that the Sinister Six would appear in the film following the mid-credits scene in Spider-Man: Homecoming that features Vulture speaking to Scorpion, yet another Sinister Six member, in prison. Scorpion (played by Michael Mando) tells Vulture that, "I've got some boys on the outside that would love to meet him [Spider-Man]... You know, take a picture, slice his throat, put his head in a dryer. And I heard a rumor that you know who he is." Vulture initially refuses to give up Peter Parker's identity to Scorpion and his "boys", who are presumably members of the Sinister Six.

Read More: Marvel Can Have Spider-Man Fight The Sinister Six in Homecoming 2

The Sinister Six were created by Stan Lee himself in 1964. The original six members, assembled by Doctor Octopus to defeat Spider-Man, were Doc Ock, Mysterio, Vulture, Kraven the Hunter, Sandman, and Electro. Later permutations of the group included other super-villains, most notably the Green Goblin, but also Scorpion, Prowler, Chameleon, Lizard, Rhino, and even Venom. The Sinister Six also had super-villain alliance spin-offs, including the Sinister Seven, the Sinister Twelve, the Sinister Sixteen, and even the Sinister Sixty-Six.

While many individual versions of Sinister Six members have appeared over the different Spider-Man franchises, the Sinister Six has not previously appeared in live-action Spider-Man films. A Sinister Six spin-off film was planned in conjunction with Andrew Garfield's The Amazing Spider-Man films, but was not pursued after Spider-Man was rebooted with Tom Holland.

This Page: Who's Already Cast In The MCU Sinister Six?

Page 2: Who Could Be The Sinister Six's Final Member?

Vulture — Michael Keaton

Spider-Man: Homecoming already introduced some villains who have appeared in different versions of the Sinister Six: Vulture, Shocker, Prowler, and Scorpion. Adrian "Vulture" Toomes, played by Michael Keaton, was the main antagonist in Homecoming, using alien technology to create hybrid alien-human weapons to sell on the black market. Vulture, along with his crew member Herman "Shocker" Schultz (Bokeem Woodbine), are sent to prison at the end of the film.

Shocker — Bokeem Woodbine

Shocker has appeared as a member of the Sinister Six (and other "Sinister" groups) in both the comics and animated television series. In the films, Herman Schultz inherits the electrical shocking device and the moniker of Shocker after Logan Marshall Green's Jackson Brice is killed by Vulture. Vulture quips to Schultz, "Now you're the Shocker."Since the Vulture is poised to return in the next Spider-Man film, it would make sense for Shocker to return as well.

Scorpion — Michael Mando

Michael Mando's character, MacDonald "Mac" Gargan, is never actually called Scorpion in Spider-Man: Homecoming, but he shares his name the villain from the Spider-Man comics. Additionally, his character sports a scorpion tattoo on his neck. Most importantly, in the mid-credits scene, Gargan makes it clear to Vulture that he is bent on killing Spider-Man as revenge, and he has a team on the outside who are willing to help him.

More: Scorpion is the Key to Bridging the MCU and Spider-Man Spin-Offs

Because they are currently in prison, it is unclear if Vulture, Shocker, or Scorpion count towards the Sinister Six. Gargan's outside crew could easily be made up of six additional villains.

Prowler — Donald Glover

Prowler, otherwise known as Aaron Davis, is a former associate of Mac Gargan. When the low-level criminal attempts to buy alien-hybrid weapons from Toomes' crew, Spider-Man captures him and demands information. Prowler tells Spider-Man that his former "crazy" employer, Gargan, is making a weapons deal with Toomes. While Prowler says that he is no longer working for Toomes, his character could be threatened or blackmailed into working against Spider-Man.

If Donald Glover is willing to return to Spider-Man, then Prowler could easily round out the Sinister Six with humor and even reluctance. Of course, that's not the only way he factors into the MCU's future. Prowler is also the uncle of Miles Morales, another iteration of Spider-Man, and Glover's character makes a reference to his nephew. Miles is set to join the MCU eventually, so Prowler will surely be back either way.

Mysterio — Jake Gyllenhaal

Academy-Award nominee Jake Gyllenhaal will reportedly play Mysterio in the upcoming Spider-Man film. Mysterio, otherwise known as Quentin Beck, was originally introduced as an adversary of Spider-Man's in the comics, although he has also faced off with Daredevil. Mysterio has never appeared in previous live-action Spider-Man films, although was reportedly set to appear in the fourth Sam Raimi's Spider-Man 4, with a popular fan theory linking him to Bruce Campbell's re-occurring character.

Mysterio is a master hypnotist and illusionist, which offers a new spin on the traditional super-villain. Additionally, Gyllenhaal's casting signals that this version of Mysterio will be a compelling and complex character, rather than a gimmicky foe in a fishbowl helmet.

Page 2 of 2: Who Could Be The Sinister Six's Final Member?

Who Could Be The Sinister Six's Final Member?

If Scorpion, Vulture, Prowler, and Shocker return, then up to four villains could be accounted for. Gyllenhaal's Mysterio would make five, but there are a number of additional Spider-Man villains who could join the ranks of the Sinister Six. Based on casting announcement that paired an older villain and a teenage boy, some fans have speculated that the Osborns (and the Green Goblin) could return; another casting call looked for a "femme fatale" character who may or may not be a part of the Sinister Six's plot.

Here are some potential villains, along with our top choices for who could play them in Spider-Man: Homecoming's sequel.

Doc Ock — Jeffrey Wright

While it's difficult to imagine any actor doing a better job as Doctor Octopus than Alfred Molina in Spider-Man 2, Westworld's Jeffrey Wright wouldn't be a bad choice to step into the mechanical arms. Wright is a masterful actor, and his soft-spoken demeanor gives way to an ocean of dark undercurrents — he could actually sell Doctor Octopus as a believable (and perhaps even sympathetic) character. The main barrier to Doc Ock is that Marvel's thus far been reluctant to re-use Spider-Man villains, and that with Scorpion and Vulture the "leader" role of the team is already hotly contested.

Kraven the Hunter — Pedro Pascal

While Pedro Pascal was recently cast in a mystery role in the upcoming Wonder Woman sequel, the Narcos star has never appeared in the Marvel Cinematic Universe - and this could be his shot. Pascal has been a fan-favorite for Kraven the Hunter, despite the fact that Kraven is Russian in the comics. An expert marksman who decides to hunt superheroes instead of big-game trophies, Pascal offers the perfect balance of physical and mental strength for the tactical and ferocious foe.

Kraven was also rumored, along with Mysterio, to have a villain spin-off film in the Sony pipeline, so his introduction in Spider-Man: Homecoming 2, which may have ruled out a straight-up MCU appearance. Now Mysterio is on the table, that may have changed with Kraven too. Of course, if we are getting Kraven, it'd more fitting in iconic comic story Kraven's Last Hunt rather than a bad guy team up.

Green Goblin — Tobey Maguire

Who could play Norman Osborn, the Green Goblin, after Willem Dafoe? Technically, Chris Cooper in The Amazing Spider-Man 2, but the Amazing reboot of the Osborns was merely a cameo. The Green Goblin is one of Spider-Man's most famous enemies, but since the character has already been rebooted twice, rebooting it a third time would need to be special in order to avoid supervillain fatigue.

One possible solution would be to reboot the Green Goblin with a nod to the original Spider-Man films by casting Tobey Maguire, the "first" Spider-Man. Maguire has focused more on producing than on acting in recent years, but the role of the Green Goblin could help to revitalize his career on the screen. After all, Michael Keaton jump-started his career again with Birdman, and has since played the Vulture in Homecoming. It could be great to see Batman and Spider-Man team up against Tom Holland's Spidey.

Venom — Tom Hardy

Tom Hardy's R-rated Venom is set to come out later this year, and it remains unclear what his character's role will be within the larger MCU. Amy Pascal and Kevin Feige had a lengthly back-and-forth of wording during Spider-Man: Homecoming's press tour, and even after two trailers the relationship between the two shared universes is unclear.

However, Venom has been a member of the Sinister Six, and so Spider-Man 2's super-villain league could be the perfect way to build Venom into the expanded MCU. If this was the case, then the obvious best choice is Hardy, even if this entire situation is an outside shot.

Chameleon — Zahn McClarnon

Chameleon, the half-brother of Kraven the Hunter, appeared in Spider-Man #1, the first Spider-Man comic. A master impersonator, Chameleon is sometimes portrayed as using elaborate masks and make-up to transform himself into other people; in other comics, he has various technological and superpowers that allow him to transform his face. In Spider-Man: Homecoming 2, perhaps the alien technology that Vulture's crew has adapted could provide a mechanism for Chameleon's transformations.

Zahn McClarnon's performances on Westworld and Fargo (season 2) have shown him to be a highly adaptable actor; as a host in Westworld alone, he has to play many different roles within the same show. McClarnon is ready to make the transition from television to the MCU, and Chameleon would be the perfect opportunity to showcase his talents as a multi-faceted actor.

Electro — Constance Wu

While Jamie Foxx played the Max Dillon version of Electro in the fairly recent The Amazing Spider-Man 2, Constance Wu could take the role in a completely different direction as Francine Frye, reimagining the character in a new way that could help to avoid a feeling of repetition and fatigue.

While Wu, who is set to star in the highly-anticipated film Crazy Rich Asians, would be a surprising choice as a villain, her nuanced and emotive performance in Fresh Off the Boat makes it clear that she could give an emotive and raw performance as Electro.

Lizard — David Harbour

It's true that Stranger Things' David Harbour is set to play Hellboy, but that doesn't mean that he can't play Curt "Lizard" Connors in Spider-Man: Homecoming 2. Harbour was, after all, in the running to play Cable in Deadpool 2, a role that eventually went to Josh Brolin. Brolin himself is proof that actors can play two comic book roles, appearing both in the Deadpool sequel and as Thanos in Avengers: Infinity WarSince Harbour is finished with filming Hellboy, he could easily be a member of the Sinister Six. Like Brolin's Thanos, Harbour's face as Hellboy will be altered enough by CGI and make-up that playing two roles in two different films shouldn't be a problem.

Harbour's characterization and physicality as an actor (recently shown when he did his signature Hopper dance in Antarctica) could elevate the character of Lizard in Spider-Man: Homecoming 2. Lizard, like a number of Spider-Man villains, doesn't easily translate from the comic book page to the screen, but Harbour could skillfully help to humanize the reptilian character. Plus, the villainous Connors would be an excellent contrast to everyone's favorite police chief-turned-dad, Jim Hopper.

Rhino — John Cena

Paul Giamatti was a surprising choice for Rhino, the mob-muscle-turned-supervillain who weighs over 700 pounds. Giamatti's version of the character used battle armor to create the larger-than-life super-strong villain, seemingly based on the Ultimate Marvel version of the character. Perhaps John Cena is a slightly more conventional choice, but the pro-wrestler and actor has yet to appear in an MCU film, despite his immense popularity.

The novelization of Spider-Man: Homecoming sets up Rhino as a member of Vulture's crew, which could hint to Rhino's involvement in the upcoming film. Cena's version of Rhino could still gain his immense strength from the Vulture and Tinkerer's alien hybrid technology, but he would also look the part of an intimidating adversary.

More: Every Spider-Man Villain Spinoff Sony is Developing

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