Stranger Things Season 4 Can Bring Back 5 Villains (& Which Is Most Likely)

From Hawkins Lab and the deeply creepy Dr. Brenner to Billy and the Mind Flayer, which of Stranger Things' many villains will be back in season 4?

Many major villains could come back in Stranger Things season 4, prompting fans to try and work out which ones will be seen again once the Netflix hit finally returns in 2022. Stranger Things has never been short on villains. Since the series debuted in mid-2016, Stranger Things has boasted an array of antagonists ranging from redeemable human characters like reformed bully Steve to inhuman monsters like the dimension-hopping Demogorgon.

As the scope of Stranger Things changed from seasons 1—3, the series also made room for more villains both human and supernatural. By Stranger Things season 2, the gang had to contend with the shady scientist of Hawkins Lab and the unhinged bully Billy as well as the Mind Flayer as well as the Demogorgon. By season 3, Stranger Things had introduced Cary Elwes’ corrupt Hawkins mayor, secret Soviet scientists and their unstoppable assassin, a body-snatching Spider Monster, and the misogynistic staff of the Hawkins Post.

There’s no denying that Stranger Thing has had plenty of memorable villains from seasons 1–3, but some of them are well and truly dead and thus unlikely to be seen again on the series. However, for every villain who is definitively dead, there are a few more (like Stranger Things season 1's villain Dr. Brenner), who may well make a comeback in the upcoming season 4. This had prompted some fans to research who these mysterious antagonists are, and which of them are most likely to return in Stranger Things season 4.

Dr. Brenner

Stranger Things season 1’s big bad Dr. Brenner was the amoral scientist responsible for Eleven’s telekinetic powers. A creepy father figure to the show’s heroine, Dr. Brenner experimented on Eleven in Hawkins Lab and either created or discovered her psychic abilities in the process. Despite being attacked and seemingly killed by the Demogorgon at the close of season 1, Dr. Brenner is almost certainly going to return, judging by Stranger Things season 4’s trailers so far. As the man responsible for Eleven’s supernatural abilities, Brenner is the most important villain in the show so far. Not only that, but Dr. Brenner’s experiments also unleashed the Demogorgon, meaning his return could tie together some enigmatic elements of both the heroine’s backstory and the lore of Stranger Things more broadly.

Hawkins Lab

The shady institution run by Dr. Brenner was still in operation after he (seemingly) died at the close of Stranger Things season 1, but was pretty much obsolete by season 3. Once taken over by Dr. Owens in season 2, Hawkins Lab operated more transparently and legitimately, with its scientists even helping Will Byers with his Mind Flayer possession. The end of the season saw Hopper adopt Eleven and the Lab seemingly shut down, but this may not be the whole story. Stranger Things season 4's "HNL Control Room" teaser makes it look likely that Hawkins Lab test subjects will escape in the upcoming season, meaning the lab must still be operating, and its scientists are likely to return. While the scene seen in the teaser could be a flashback to Eleven’s past, it is more likely that the mass breakout occurs during the action of Stranger Things season 4, since it seems impossible for numerous test subjects to have escaped alongside Eleven and not kept in touch.

The Russians (& Grigori)

The shady institution run by Dr. Brenner was still in operation after he (seemingly) died at the close of Stranger Things season 1, but was pretty much obsolete by season 3. Once taken over by Dr. Owens in season 2, Hawkins Lab operated more transparently and legitimately, with its scientists even helping Will Byers with his Mind Flayer possession. The end of the season saw Hopper adopt Eleven and the Lab seemingly shut down, but this may not be the whole story. Stranger Things season 4's "HNL Control Room" teaser makes it look likely that Hawkins Lab test subjects will escape in the upcoming season, meaning the lab must still be operating, and its scientists are likely to return. While the scene seen in the teaser could be a flashback to Eleven’s past, it is more likely that the mass breakout occurs during the action of Stranger Things season 4, since it seems impossible for numerous test subjects to have escaped alongside Eleven and not kept in touch.

Billy

Judging by the Stranger Things season 4 episode title “Dear Billy,” it seems likely that Dacre Montgomery’s unhinged, scene-stealing bully will be back. However, he was pretty definitively dead at the end of Stranger Things season 3, meaning these appearances may be limited to flashbacks from his sister Max. It is not inconceivable that Billy could have survived his apparent death at the hands of the Spider Monster since the rules followed by the interdimensional monsters of Stranger Things have never been clearly outlined and Eleven did make it through her season 1 confrontation with the Demogorgon. However, Billy was skewered through the torso and doesn’t have any of Eleven’s superpowers to fall back on, making it likely that the Stephen King-inspired Stranger Things villain is likely gone for good (save for flashback cameos).

The Mind Flayer

The primary (non-human) antagonist of the show so far, the Mind Flayer has been behind the horrors of every Stranger Things season in some guise or another. In season 1, the entity went largely unmentioned, as a single Demogorgon was more than enough trouble for the modest early episodes. As Stranger Things season 2 offered a more ambitious plot, the Mind Flayer became a major villain that threatened Will’s life and sanity while also controlling a small army of Demogorgons. By Stranger Things season 3, the Mind Flayer returned as the Spider Monster, and its defeat via Billy’s self-sacrifice hardly seems sufficient to keep the interdimensional monster down for good.

No matter how much Stranger Things season 4 changes the show’s formula, the Mind Flayer’s return is all but inevitable. The villain is responsible for every supernatural threat seen in the series so far and offers a greater scope antagonist who is always present even when the heroes defeat each season’s threat, giving the show an epic scope without sacrificing its small-town setting. As such, Stranger Things season 4 will need to bring back the Mind Flayer in one form or another, although the question of whether it will be a multi-story beast like the Spider Monster or a smaller threat like the Demogorgons of earlier seasons remains to be seen.