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