The official Stranger Things companion, World Turned Upside Down, reveals that the show was very different when it was first picked up by Netflix. When Stranger Things season 1 was released back in 2016, nobody realized that it would become a cult classic. Its popularity was mostly driven by word of mouth, and the show's tremendous performance simply blew the cast and crew away. The Duffer brothers were particularly delighted when some of their heroes, most notably Stephen King, took the time to praise their series on social media.

Netflix and Century Books have partnered together to release the first official Stranger Things companion, a book that explores how the show gradually took shape. It stresses just how much of a risk Netflix was taking when they signed off on the series. "We were green-lighting a season of television from two creators who had no track record whatsoever, and we're going to give them, say tens of millions of dollars to make a season of television," Matt Thunell observed. "This was always terrifying. It was a trial by fire."

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Stranger Things had been turned down by 10-15 different networks and streaming services before it was greenlit by Netflix. Ironically, the two main reasons were the '80s setting and the fact it's a show starring kids but not aimed at teenagers - both factors that would prove key to the show's success. But, while those details remained the same, "World Turned Upside Down" reveals just how different the original version of Stranger Things really was.

Welcome to Montauk

The Duffer brothers wrote the script for their pilot in a matter of weeks, but it wasn't even called Stranger Things. Instead, it bore the title Montauk, named after the sleepy Long Island town on which it was originally set. The location was intended as a tribute to the Duffers' favorite film of all time, Steven Spielberg's Jaws.

Conspiracy theorists will recognize the name of Montauk. According to legend, the Montauk Air Force base was the center of a series of experiments and conspiracies, with scientists attempting to unlock secrets of parapsychology ranging from telepathy to time-travel. It all seems to have originated with Preston Nichols, a man who claimed to have discovered repressed memories of his own involvement in the project. He teamed up with author Peter Moon to pen a series of books, known as the Montauk Project series, which explore the conspiracy in detail. They cover everything from faked Moon landings to "a hole ripped in space-time" back in 1983.

Although the setting was completely different, it's not hard to see the broad similarities between the Montauk Project and the plot of Stranger Things - right down to the hole torn in the fabric of reality itself. In the end, though, when the Duffer brothers headed to Long Island to begin filming, nothing quite seemed to work. The community itself, which lay at the heart of their script, looked nothing like they had imagined. The Duffers realized it would be a better idea to switch things up and center the plot in the kind of suburban town they'd grown up in, and knew so well. "Even though it was heartbreaking at the time," Ross Duffer observed, "it made for a better show."

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Stranger Things Was Originally A Lot Darker

In addition to the script for the pilot, the Duffer brothers approached Netflix with a 23-page "look book" that would serve as a companion for their pitch. This document summarized the story, and gave character breakdowns and biographies. Crucially, it was supported by pictures from the films that had inspired Stranger Things - stills from films ranging from Stand By Me to Nightmare on Elm Street. But the show described by the look book was a lot darker than the final version, dipping into the horror genre and drawing inspiration from the works of Guillermo del Toro, Clive Barker, and - most significantly of all - H.R. Giger. Giger is best known for creating the Xenomorphs of the Aliens franchise.

But it looks as though Stranger Things may yet become a much darker show. "If you look at the Harry Potter films," Matt Duffer explained, "as the kids grow, the series becomes a little more adult, a little bit more mature. That was something we wanted to do." That's why there's a tonal difference between Stranger Things seasons 1 and 2, and that idea will presumably continue on into the third season as well. The book teases that season 3 will draw inspiration from the body horror of David Cronenberg and John Carpenter's The Thing. So it may be that Stranger Things will gradually become the series the Duffers first pitched.

Page 2: The Upside-Down and the Death of Steve Harrington

Stranger Things Didn't Originally Explore the Upside Down

The Upside Down was originally called "the Nether," and surprisingly the Duffer brothers didn't intend to explore this mysterious plane of reality at all. Their idea was a simple one: that what we don't see is often scarier than what we do. That's especially the case when the unseen is just out of sight, leaving the imagination reeling. It was only during production that this changed; the Duffers had filmed roughly five hours' worth of the story before they realized to expand the narrative, to send their stars into the Upside Down and reveal just what this place was like. It's fascinating to imagine how differently the story would have played out without going into the Upside Down; would Will even have been rescued at all?

Naturally, the late-in-the-day decision to head into the Upside Down posed a real challenge. It meant the production team had to create an entire reality at speed. What's more, the Duffers were keen on maintaining the same approach they'd used to date, with a minimum of visual effects. They drew inspiration from the 1999 video game Silent Hill, which led them to create the Upside Down by using color correction, ash, and deteriorating buildings. The strange particles floating through the air are lifted from Ridley Scott's Alien; they're actually dandelion seeds.

Related: How Stranger Things Can Make Its Worst Episode The Best In Season 3

Several Major Characters Originally Didn't Survive Stranger Things Season 1

Eleven in Stranger Things Netflix series

By now, it will be clear that the Duffer brothers were reacting to their instincts all the way through production. Incredibly, those instincts even decided who would live and who would die. Steve Harrington, for instance, was envisioned as a much harsher bully - and one who got killed off partway through the season. Fortunately, Joe Keery was cast for the role, and the Duffers decided he was too good an actor playing too interesting a character. "Honestly, the day Steve Harrington dies is the day I walk off this show," executive producer Shawn Levy recently told TVLine. "I literally feel that we were walking along and we stumbled onto a gold mine with Dad Steve."

But there was one other major character who was planned to die: Eleven. The end game was always that Eleven would sacrifice herself in order to defeat the Demogorgon and save the day. The Duffer brothers only changed their plans when they realized there was a good chance Stranger Things would be renewed. "We needed to leave it more up in the air," Ross Duffer explained, "because deep down we knew the show just wouldn’t really work without Eleven. And at that point, we knew how special Millie was. If there was going to be more Stranger Things, Eleven had to come back."

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