'We call this our Game of Thrones season': Stranger Things cast promise dark times ahead

Netflix David Harbour returns as Jim Hopper in 'Stranger Things' season 4.

Ross Duffer, standing by his brother and fellow Stranger Things creator Matt, slips himself up. The duo are recording a presentation, shown to press during filming of the show in June of last year, to set up the fourth and penultimate season of their Netflix hit. "I think our goal with the show is always to try something different every year and make sure the show is evolving, and that comes naturally in a lot of ways because our kids are growing up," he says.

Kids? Millie Bobby Brown, who was first cast as the telekinetic waffle-loving girl-of-few-words Eleven in Stranger Things when she was 12, is now a superstar at the age of 18. Sadie Sink, performing on a high school dance set on the season 4 production, is now four years older than when she first appeared on the supernatural drama at 15. "I can't even actually call them kids," Ross clarifies. "They are like full-blown young adults now."

Finn Wolfhard, now 19, equates the cast's experience to the stars of Harry Potter, who also grew up before our eyes on screen. "As those movies went on, the darker they went. That's kind of where we're at now," Wolfhard says. "Inherently it becomes darker every season. It gets funnier, it gets scarier, it gets more dramatic," he adds. "I think that just comes with all of us growing up and getting older. We're not all going to be in mop top wigs when we're 40 years old, screaming about demogorgons and stuff."

Ross confirms the show's horrors are getting progressively more intense as it reaches its conclusion. (Netflix announced in February that season 4 will be split into two parts, while season 5 will bring the show to an end.) Keeping with the Harry Potter analogy, this year's episodes are like the Goblet of Fire or Order of the Phoenix era, though Ross has a different cinematic reference: "We thought that this was a good year to put them in a full-fledged Nightmare on Elm Street-esque horror film."

Netflix (L to R) Argyle (Eduardo Franco,) Jonathan (Charlie Heaton), Eleven (Millie Bobby Brown), Will (Noah Schnapp), and Mike (Finn Wolfhard) in Netflix's 'Stranger Things' season 4.

The Duffers like to think of season 4 as their Game of Thrones season, and not just because the stakes are amping up. They could easily have their own opening titles sequence that highlights all the different areas of the map where the characters are operating, set to the driving sound of a Ramin Djawadi soundtrack.

Joyce (Winonya Ryder) decided to leave Hawkins behind and take her family, including Eleven, to California. But settling into a new school — just as many of the teens are facing the horrors of high school for the first time — isn't without its growing pains.

Jonathan (Charlie Heaton) finds a new bestie in quintessential stoner and Surfer Boy Pizza delivery guy Argyle (Eduardo Franco), but a long-distance relationship with Nancy (Natalia Dyer), who's still in Hawkins, remains trying. "I think that's coming terms with what the future looks like for them as people and them as a relationship," says Heaton. And while Eleven, still without her powers, might like to pretend she's making friends — at least that's what she tells Mike (Wolfhard) in her letters — bullies will always sniff out the socially vulnerable.

Franco believes the new California setting is "so different from what has been shown" in previous seasons of Stranger Things. He embraces his role as the comedic relief, but he remarks, "It's supposed to be exactly like E.T., that vibe."

"Fast Times. Lord of the Flies," Heaton adds. "We obviously, over the years, have varied, but it was the '80s nostalgia, where this is a different kind of take on an '80s representation."

Netflix Joyce (Winona Ryder) and Murray (Brett Gelman) in Netflix's 'Stranger Things'.

If California is more E.T., then Joyce and Murray (Brett Gelman) are going on their own Indiana Jones-style adventure. Joyce receives a mysterious package in the mail, one that contains a Russian doll and a stitched together letter that claims Jim Hopper (David Harbour) is secretly alive and trapped in Russia. So, she enlists conspiracy theorist Murray on a mission to the snowy wasteland of Kamchatka to bust him out. This sets them on a course to meet a man named Yuri (Nikola Djuricko), a seedy Russian smuggler.

Gelman also thinks of his Joyce-Murray arc as akin to Star Wars. "That Luke-Leia-Han dynamic I think really is an energy that's constantly flowing through my scenes with Winona and David and Nico," he says. Hawkins, meanwhile, is always gonna Hawkins.

Everyone back in the hometown is splintered in some way. Max (Sink) is still dealing with the death of her brother, which has made her become a loner entering high school. Steve (Joe Keery) and Robin (Maya Hawke) are doing their own thing working at the local video store — mostly chasing after their crushes. Lucas (Caleb McLaughlin) knows he has the chance to be popular when he makes the high school basketball team, while Mike and Dustin (Gaten Matarazzo) are still playing Dungeons & Dragons. They're now part of the Hellfire Club, Hawkins High's D&D group run by '80s metal head and dungeon master Eddie Munson (Joe Quinn).

Netflix Joseph Quinn plays Eddie Munson, dungeon master of the Hawkins High Hellfire Club, in 'Stranger Things' season 4.

"Hellfire Club is kind of a dark D&D club of just all the outcasts and rejects," Wolfhard explains. "It's good because [Mike's] found his little calling at school. He has something, finally. I think there's also an implied darkness to it that makes him feel pretty cool."

The Duffers promise the Hellfire Club will be a big part of Stranger Things season 4 as the storyline tackles the Satanic Panic, which stoked fears in the '80s and '90s and linked things like D&D to devil worship and the occult. "To some people in Hawkins, they don't think that it's an innocent game that they're playing, but that there is something more sinister beneath the surface," Ross says. That adds to the community's fears when tragic events start to occur yet again.

It's been six months since the events of season 3 and a new evil has risen to shatter the illusion of normalcy that has fallen over the town. Vecna, the new demo-creature on the block which resides in a part of the Upside Down, is a name known to players of D&D. He's a wizard who used magic to become an undead creature called a lich, and from there he ascended to godlike status.

Netflix Vecna, the new demo-creature, is revealed in the latest 'Stranger Things' season 4 trailer.

Adding another level of chills and thrills is the Creel House, the pseudo haunted mansion of the season. Here's where the Duffers' A Nightmare on Elm Street reference becomes more overt: Robert Englund, a legend of the horror genre who played the serial killer of your nightmares Freddy Krueger in those films, takes the role of Victor Creel.

In the 1950s, Victor moved into the house in question with his wife and two kids, and then strange things started to happen — followed by even stranger things. Authorities don't fully know what happened, but after committing a gruesome murder, Victor was committed to a psychiatric hospital and has been there ever since.

Dyer, whose character Nancy is on the hunt for clues to solve the current mystery in Hawkins, confirms she's had scenes with Englund. "He brought a real enthusiasm to his role, and honestly, it was just an honor to watch him work," she says. "The role that he plays is just really interesting. I can't say that much about it, but he was so lovely and kind and sweet and really gave such a great performance. I'm really excited to see it on the screen."

Netflix 'A Nightmare on Elm Street' horror icon Robert Englund plays Victor Creel on 'Stranger Things' season 4.

"Part of the drive and tension of this season is that we have this big new evil emerge in Hawkins and for the first time ever, Eleven is not there," Ross says. "And not only is she separated by distance, but at the end of season 3, she's lost her powers, so even when she learns about what has happened in Hawkins, she is unable to help them in the same way she has before."

Eleven does find a way she can return her powers, but it means revisiting her past, including some things she would like to forget while a child in Hawkins Lab. That's why Matthew Modine is back as Dr. Martin Brenner, a.k.a. Papa.

Brown says those scenes at Hawkins Lab were very difficult for Eleven in season 1. Now in season 4, "you get to see Eleven in the darkest state she's ever been," the actress says. "This has definitely been the hardest season I've ever filmed. There have been some of the scariest, scariest things that I've ever seen as a human, which you guys will get to see, for sure."

Netflix Millie Bobby Brown's Eleven unleashes in 'Stranger Things' season 4.

Season 4 will become crucial to understanding what the Duffers have been doing with this show since the beginning. It's not just about learning more about Eleven's backstory or learning about what Vecna is up to. "What occurs in [Creel House] is pivotal to understanding what has been happening in Hawkins all of these years," Ross mentions. Brown, too, confirms, "It always leads back to the Upside Down. Eleven's character arc this season is incredible, and you guys definitely get to see things that you have been questioning. You get answers."

For as much as the cast have grown, they admit there are some things that have genuinely freaked them out. "I would definitely say [season] 4 is the scariest and the darkest, easily," Wolfhard says. But that's what he loves about the show. "It is just constantly breathing and changing, like it's its own monster."

Stranger Things Volume 1 premieres on Netflix May 27, with Volume 2 set for July 1.

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