Stranger Things 'Demogorgon': Every Stage of The Series' Monster Explained

Now that Stranger Things Season 5 Volume 1 has arrived, released on 26 November 2025, you might be curious about how the monsters in the series have evolved. Among the many mysteries and monsters, one creature still looms large: the Demogorgon, the gang's very first adversary and one of the show's most iconic horrors.

Here's a detailed stage-by-stage look at where each form appeared in the series, along with descriptions and fun facts.

The Demogorgon's Life Cycle: Appearance, Details, and Fun Facts

The Demogorgon is a creature of the Upside Down, evolving from a tiny larva to a terrifying humanoid predator.

The iconic design of the Demogorgon — including its humanoid body, sinewy limbs, and flower‑like mouth — was created by Aaron Sims Creative, who developed the concept art and visual design for the series.

Stage 1: The Larva (Slug‑like)

In Season 1, Episode 8, entitled 'The Upside Down', Will Byers, after spending time in the Upside Down, begins to show signs of possession. At the climax, he coughs up a small slug-like larva, hinting at the first stage of the Demogorgon's life cycle.

This larva is never seen moving independently, but its presence shows that the Upside Down's creatures can implant or influence humans in early stages.

Details:

• Tiny, translucent, and wormy in shape with pale yellow spots
• Has a slimy texture and moves slowly, mostly surviving by absorbing nutrients from its host or environment
• Almost imperceptible to the naked eye, giving it a deceptively harmless appearance

This stage eventually molts into the pollywog, beginning its journey to becoming a fearsome interdimensional predator.

Fun fact: The larva's 'slime' sound effects were created by squishing gelatin in a water bath on set.

Stage 2: The Pollywog

In Season 2, Episode 2, 'Trick or Treat, Freak', Dustin finds a small tadpole-like creature in his trash, which he names D'Artagnan or Dart for short. In Episode 3, 'The Pollywog', Dustin keeps Dart in a fish tank and starts feeding it. The creature shows early intelligence and mobility, revealing its predatory instincts.

Details:

• Tadpole-like, green-grey skin with small claws and a developing tail
• Tiny mouth forms for feeding; begins growing rudimentary limbs
• Sensitive to heat; even a table lamp can make it uncomfortable
• Shows early preferences, such as liking chocolate bars for food
• Unlike later stages, the pollywog is mostly harmless and focused on growth rather than hunting
• With enough food, it gains mass, develops hind legs, and sharp teeth to transition to the next stage

Fun fact:The pollywog's squeaky movements were inspired by a combination of baby frogs and sound designer Craig Henighan gargling water, giving it a wet, otherworldly feel.

Stage 3: The Frogogorgon

While not explicitly named on-screen, the Frogogorgon is described in fandom documentation and visual guides as the stage between pollywog and Catogorgon. Visual cues appear when Dart begins to develop limbs and a more defined head.

Details:

• Amphibious, frog-like form with mottled green-grey skin and a short stubby tail
• Bulging eyes and small, developing limbs; slightly more muscular than the pollywog
• Moves with a hopping or crawling motion; agile predator
• At this stage, it mirrors real-world amphibian metamorphosis, giving the creature a biologically plausible evolution

Fun fact: The frogogorgon's limp is actually not intentional, but it was a rendering error. The producers just decided to keep it, and its hopping noises were made by stretching rubber tubing and mixing it with reversed frog croaks for a slightly alien tone.

Stage 4: The Catogorgon

The Catogorgon stage is hinted at on-screen when early-stage Demodogs show quadrupedal movement with partially opened flower-heads.

Details:

• Quadrupedal, lean and muscular; skin dark grey with streaks of green
• The head begins to form the characteristic petal-like mouth, partially open with tiny teeth
• Limbs fully functional for running and hunting; body sleek and agile
• Bridges the juvenile Demodog and adult stages, showing a gradual escalation of strength and hunting ability

Fun fact: It is so named since it is the size of a cat, but it ate Dustin's cat, Mews. Its early growls were created by layering recordings of domestic cats, dogs, and manipulated human sounds to create a hybrid alien predator noise.

Stage 5: The Demodog

In Season 2, Episode 6, 'The Spy', Dart is now a Demodog, walking on all fours and showing full predatory instincts. In Episode 7, 'The Lost Sister', other Demodogs are seen roaming Hawkins, hunting humans and animals in packs. It is also the major threat of the season.

Details:

• Juvenile predator; elongated limbs, roughly humanoid torso, but walks on all fours
• Dark grey skin with lighter veins; flower-mouth partially open, showing rows of small, sharp teeth
• Agile, fast, and able to hunt in coordinated groups; furrows along limbs for muscle definition
• They are bulletproof and can already kill a human
• Demodogs show that even juvenile Demogorgons are lethal and capable of coordinated attacks

Fun fact: It is also voiced by Henighan. To make the sound, he added a howler monkey to his voice. The Demodog suits were also made from a combination of latex, foam, and practical prosthetics, with animatronic elements for the mouth.

Stage 6: The Adult Demogorgon

In Season 1, Episode 1, 'Chapter One: The Vanishing of Will Byers', the adult Demogorgon is glimpsed at the lab in the Upside Down. Its full form terrorises Hawkins in Episodes 4, 5, and 8, killing Barb, pursuing Will, and confronting the main group.

Hopper fights a Demogorgon while imprisoned in the Russian facility in Season 3, Episode 8, titled 'The Battle of Starcourt.'

It's also the one who appeared and attack Holly Wheeler and her mother, Karen in Season 5

Details:

• Fully grown humanoid monster; tall and muscular, around 7-8 feet tall
• Dark leathery skin with sinewy muscles; flower-like head fully opened, lined with jagged teeth
• Limbs elongated and powerful; clawed hands and feet; agile yet terrifying in movement
• Bulletproof but weak to fire, melee weapons like swords, knives, and axes, and when it opens its mouth
• A single one can destroy a town

Fun fact: The adult Demogorgon design draws inspiration from classic horror monsters and represents the ultimate form of the species' life cycle. The Demogorgon's iconic flower-mouth roar was created by layering Henighan gargling water, pig squeals, and reversed animal growls — combined with subtle digital enhancement for extra terror.

Hawkins' Monster Evolution

From its tiny slug-like beginnings to the towering, fearsome predator of the Upside Down, the Demogorgon remains one of Stranger Things' most iconic and terrifying creations.

With every stage carefully designed and brought to life through a mix of concept art, practical effects, and inventive sound design, it's no wonder the creature continues to captivate fans — proving that in Hawkins, danger truly evolves.