‘Stranger Things’: Everything We Know About the Upside Down

Donna Dickens
TV Netflix
TV Netflix Stranger Things Sci-Fi

In America, one of the biggest holidays of the year is Independence Day, celebrated on the 4th of July. For fans of the Netflix original series Stranger Things, the holiday weekend will be particularly joyous in 2019 as the third season of the show drops on July 4th. While the first season took place during November of 1983 and the second during Halloween of 1984, showrunners the Duffer Brothers are changing things up for the third season, which takes place during the summer of 1985, giving fans their first look at how the creatures of the Upside Down react to hot Indiana weather.

But the biological reaction of an alien species that can be burned by simple sunlight in their larval stage to the humid hell that is sweltering Midwest summers is one of innumerable things neither the residents of Hawkins, Indiana nor the viewers know about the mysterious Upside Down. In fact, despite two full seasons in which characters have traveled between our world and the home of the Demogorgon, little and less is known for sure about Upside Down. But using context clues both within the Stranger Things universe and from Dungeons & Dragons lore helps hone in on what exactly Eleven and the gang are dealing with.


The short answer to the question above is that no one knows, and the 1980s technology used by the Hawkins National Laboratory limits them when it comes to finding answers. At this point, it is assumed both in-universe and within the lore that the Upside Down is an alternate dimension. Though it is possible that it is instead a parallel universe, a different moment in our timeline (since several Hawkins buildings remain standing in the Upside Down), or an alien world we’ve somehow connected to via bio-organic wormholes.

The Demogorgons, the Mind Flayer that appears to control them, and Eleven herself all have the ability to rip “portals” or “gates” in space-time through which to enter and exit the Upside Down. But while the main gate the Mind Flayer opened beneath Hawkins remains a gaping wound, the smaller portals opened by the Demogorgons and Eleven eventually close. The phrase “gaping wound” is most apt as the gates appear organic in nature, with sinew and mucous membranes reminiscent of amniotic sacs. When Nancy Wheeler discovered a gate set in a tree, it was knitting itself back together. Whether this is the Upside Down itself healing a wound in its boundary or a representation of physics in a way the human mind can comprehend is currently unknown.

It’s important to remember in the first season, Eleven demonstrates how our world is connected to the Upside Down by literally turning the Dungeons & Dragons game board over. A simple, yet effective metaphor. Later, Dustin compares the Upside Down to the Vale of Shadow, a D&D realm that was created by the Duffer Brothers for the show, but which bears a striking resemblance to the Plane of Shadow, also known as Shadowfell.


Trying to summarize the complex lore of Dungeons & Dragons in an article about Stranger Things is a fool’s errand. In brief, there are multiple planes of existence within the D&D lore but each one has gone through many iterations over the decades. For example, the Plane of Shadow alone has at least three independent existences: one within the main continuity, one within the Forsaken Realm continuity, and one within the Eberron continuity. The great thing about D&D is its flexibility, allowing Dungeon Masters to add and remove elements as needed for the story they are telling.

The main thread that ties all these versions of the Plane of Shadow together though is the same as the one that pops up in Stranger Things: a pocket dimension that shares a border with the Material Realm (our world). The Shadow Plane is a reflection of our world, created out of cosmic energy beyond the understanding of mere mortals. There is no sunlight and no stars, just a vast expanse of toxic grey horizon. Much like the Upside Down, terrain within the Shadow Plane will look familiar to those who enter from our world. Dark and decaying analogs to buildings, forests, and roads appear. That tracks with the eerie and abandoned version of Hawkins the kids find in the Upside Down.

However, being a place of magic means time and distance work oddly. Those who visit the Plane of Shadow can find themselves lost great distances become small or buildings and natural terrain morph and disappear. Sometimes whispers can be heard coming from the Material Realm to those who wander in the Shadow, same as in the Upside Down. While there are no specific references in D&D, to this writer’s knowledge, about the effect of electromagnetism in the Plane of Shadow, Stranger Things imbues the Upside Down with the ability to cause lights to flicker and pop as creatures pass by. It is in this manner that Will is able to communicate with his mother in Season One and how the kids are able to track Joyce and Hopper through the Byer home when the adults are searching for Will in the Upside Down.

Much like most versions of the Shadow Plane, the Upside Down appears to be toxic to humans who linger within it. While Nancy Wheeler survives a short visit without (apparent) side effects, Will Byer is weakened by prolonged exposure, as well as becoming the host body for a Demogorgon larva. All adults entering the Upside Down wear full hazard suits, though whether this as a “safety first” precaution or due to hard lessons learned in previous excursions is unknown. Hopper’s discovery that the Upside Down is investing Hawkins, killing any plant life above the tunnels, indicates any fear of contagion was well-founded.


So just what kind of creatures not only survive but thrive in a place like the Upside Down? As far as anyone knows, only Demogorgons and the Mind Flayer inhabit the gloomy wastes. Both creatures are named by the kids, based on creatures in Dungeons & Dragons. Before looking to their namesakes for clues, let’s first examine the facts Stranger Things has laid out for each species.

The most important thing to know about the Demogorgon is that it is able to pick up on psychic energy (and appears to have limited telekinesis). Without that biological asset, the original creature that terrorized Hawkins in Season 1 would have never sensed Eleven touching it through the Void. Once alerted to the presence of our world, the Demogorgon utilizes an unknown process to rip holes in the membrane between the Upside Down and Earth to hunt. Considering both humans — Will and Barb — the creature brought to its lair were used as incubators for larval Demogorgons, it appeared the original creature was also reproducing. This was confirmed in Season 2 when Dustin finds a juvenile Demogorgon he names Dart.

Within the lore of Dungeons & Dragons, the Demogorgon is a Demon Prince. Bipedal in nature, the creature has two long necks resembling snakes with mandrill heads atop each one. While the Stranger Things Demogorgon doesn’t physically resemble its namesake, it was the last encounter the boys had in D&D before Will’s disappearance and the monster’s arrival. From the perspective of these kids, an exact match was a quibble.

Little and less is known about the other confirmed species from the Upside Down: the Mind Flayer. At least 50 stories tall and resembling a tentacle monster from Lovecraft’s nightmares, the Mind Flayer spends most of its time in Season 2 attempting to take over Will Byers’ body for to once again try to eradicate humanity. In control of the more animalistic Demogorgons, the Mind Flayer is an intelligent creature of immeasurable age but one with a weakness: fire.

Within D&D, Mind Flayers (since renamed Illithids) are a psychic race of Cthulhu-looking humanoids. Aggressive tyrannical slavers, Mind Flayers travel the multiverse leaving horror and devastation in their wake. It is no wonder the boys would choose this name for the eldritch abomination that lords over the Upside Down.

There could also be an unknown third native species to the Upside Down. When Eleven makes first contact with the Demogorgon, it was eating the innards of a large, alien egg. As of this writing, it is unclear what kind of animal hatches from such an egg. Perhaps Season 3 will bring answers. It’s a safe bet it will bring more questions.

Stranger Things 3 premieres July 4th on Netflix. 

Donna Dickens
Donna has been covering genre entertainment for nearly a decade. She is a mom, a wife, a Slytherin, a Magical Girl, a Rebel, and a fan of House Tyrell.