Nobody expected "Stranger Things" to be such a huge hit, but it turned out to be a cultural phenomenon. Its '80s stylings struck a chord with many of us, while its obvious inspiration from some of the decade's biggest sci-fi/horror classics made the show an overnight success. But it's the mythology of "Stranger Things" that kept us hooked.

First, there's the Upside Down, the weird alternate dimension that's home to some of the most terrifying horrors the world had ever seen. Not to mention the mysterious power plant on the edge of town. Throw in some strange occurrences and an otherworldly monster, and we've got a recipe for chilling success. And that's just the start.

"Stranger Things" has since taken on a life of its own, expanding its eerie tale into a rich mythology of Cold War experimentation, psychic children, and a whole range of horrors that lurk in the night. Hawkins, Indiana is now home to some of the weirdest tales you can find in the American Midwest. And while the tales keep us coming back for more, it's kept the folks at Netflix on their toes. After all, there's a lot of mythology to keep track of.

Where did the Demogorgon come from? What happened to Dr. Brenner? Where does Eleven get her powers? Some of these have been answered in the show, but with more and more questions, Netflix kept asking the show's creators one thing: "Can you explain all this mythology to us?"

Dungeons & Dragons & The Upside Down

It all started with a simple premise: a boy goes missing and ends up stuck in another dimension. That's easy enough to keep track of, right?

Well, the story soon turned into a tale of otherworldly demonlike monsters, a shadowy science lab outside town, and a psychic girl who might be the missing boy's only chance at getting out alive. Plus, countless Dungeons & Dragons references that would mean very little to the non-geeks among us.

The Duffer Brothers wrote a "Stranger Things" production bible to keep track of it all. Ross Duffer explained at 2022's Deadline's Contenders Television panel:

"We wrote this giant 20-page document, which talked about everything in terms of what was going on and what exactly the Upside Down was. And then each season we're just sort of peeling back the layers of that onion, so to speak."

Of course, by the end of season 1, there were more questions than answers. Will Byers had been rescued from the Upside Down, but we still had no idea what the place really was. Then there's the fate of Dr. Brenner, the scientist who experimented on Eleven at the Hawkins National Laboratory. After being attacked by a Demogorgon, he was presumed dead … but was he? Last but not least was the mysterious slug coughed up by Will Byers in the final moments of the last episode. What was going on? Had Will brought back a piece of the Upside Down? Some of that would be explained … but not until season 2.

The Rise Of The Mind Flayer

It turns out "Stranger Things" had a big bad villain all along — and it wasn't the Demogorgon. That would be the Mind Flayer, the shadowy creature seen looming over Hawkins at the start of season 2. And it had big plans for Will Byers.

Plaguing Will with terrifying visions of the Upside Down, the Mind Flayer planned to cross over to our dimension. But it needed a host. So after encountering Will during one of his visions, the Mind Flayer began to take over the boy's mind and body.

Why does it want to cross over into our world? Its ultimate goals remain unknown. But the Mind Flayer posed a huge threat to the town of Hawkins and the rest of the world. Thankfully, the gang eventually found a way to defeat it. Briefly gaining control of his body, Will tapped out a message in Morse code: "CLOSEGATE". The gate to the Upside Down would need to be sealed to sever Will's connection to the Mind Flayer … and so Hopper and Eleven set off to the Hawkins National Lab to close the gate for good.

Although Eleven was able to use her psychic powers to close the gate, the citizens of Hawkins remain unaware that the Mind Flayer had survived. An ominous scene at the end of season 2 showed the monster looming over Hawkins Middle School. But would the Mind Flayer be back?

The Battle Of Starcourt Mall

Essentially, yes. The Mind Flayer wasn't giving up quite so easily. But the kids have growing up to contend with, too.

"Stranger Things" season 3 saw the gang's dynamic complicated as they begin to grow older and more mature. But don't worry, it's not just about growing pains. There's a healthy dose of terrifying horror, too.

The Mind Flayer has returned after a part of its essence, trapped in our world after the gate was forced shut, and it's given a second wind. That's right — a gate to the Upside Down has opened once again, but this time it had all the hallmarks of a Cold War invasion. The Russians, pitching up in Hawkins beneath the newly built Starcourt Mall, had reopened a gate to the Upside Down, and this time, the Mind Flayer was going big. Flaying humans across the town, it melted their bodies down to create a physical proxy for itself in our world — a hellish amalgamation of human and rat flesh. It was ultimately sent packing, but not before a few casualties.

And so season 3 left us with even more questions. Will the Mind Flayer be back? Has Hopper really died? Will we ever see Dr. Brenner again?

A New Nightmare

"Stranger Things" season 4 is just around the corner, but we already have some answers. Yes, Hopper is alive. Hooray! But judging by a recent trailer, it looks as though his encounter with the gate in season 3 has transported him to Russia, where he's imprisoned in a terrifying gulag.

And it looks as though "Stranger Things" will finally get into some of the bigger mysteries at the heart of the show, too.

"This season, we really wanted to really get into it and [reveal] some of those answers," said Ross Duffer at Deadline's Contenders Television panel. "But to do that properly, we needed time, so it just became bigger and bigger."

Going by what's in the trailer, there's a lot to dig into, too. We've got flashbacks to Eleven's past, which may give us an even bigger glimpse at the nefarious experiments, plus an all-new monster known as Vecna. It's another Dungeons & Dragons reference, and it's going to need some explaining. Matt Duffer said at the panel:

"I don't think we have an episode clocking in under an hour — even in season 1 there were episodes that were like 35 minutes. You kind of forget that. This season, they're very long, so I think it's almost double the length of any season. So that's one reason it's taken so long. It does have this sort of epic quality to it. It's a different feel, for sure."

There's a lot of mythology to explore, for sure. Perhaps we'll get to the bottom of the Upside Down once and for all. Here's the official synopsis:

"It's been six months since the Battle of Starcourt, which brought terror and destruction to Hawkins. Struggling with the aftermath, our group of friends are separated for the first time — and navigating the complexities of high school hasn't made things any easier. In this most vulnerable time, a new and horrifying supernatural threat surfaces, presenting a gruesome mystery that, if solved, might finally put an end to the horrors of the Upside Down."

"Stranger Things" season 4 debuts on May 27, 2022.

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The post The One Question Netflix Kept Asking About Stranger Things After Season 1 appeared first on /Film.