STRANGER THINGS 5’s Big Cameo….Sure Was a Choice!

And that choice WAS NOT Eddie Munson. Come on, guys! It could have been Eddie Munson. Instead, Stranger Things 5, Volume 1 brought back quite possibly the LEAST requested character of all. Throughout Volume 1, Stranger Things 5 teased a major revelation, hinting that Linda Hamilton’s Dr. Kay was keeping someone or something behind a locked vault door. And that character COULD have been Eddie Munson. Instead, what we got was pure Stranger Things shenanigans. So, who was behind Dr. Kay’s locked vault door? In the end, Stranger Things 5, volume 1’s big cameo, its promised super-powerful surprise character, was none other than Elven’s “sister” Kali Prasad, also known as Eight. And it turns out Kali/Eight was introduced in what is widely considered to be Stranger Things‘ worst episode.

Who Is Kali Prasad/Eight in Stranger Things?

It’s been a very long time since we saw Kali/Eight on Stranger Things, yet, somehow, here she is again in Stranger Things 5.

Kali first appeared in Stranger Things 2, episode seven, “The Lost Sister,” presumably to shed some light on Eleven’s past and powers. Like Eleven, Kali was taken by Doctor Brenner at a very young age and kept at Hawkins Lab in Indiana. She was one of the several other children with abilities, whose mother had presumably been part of the MKUltra experiments where Brenner infused women with Henry Creel/Vecna/One’s Flayed blood in order to induce powers and abilities in them. Eight was also seen in one of the Stranger Things‘ most replayed flashbacks, playing with Eleven as her birth mother tries to break into the lab and reach out to her.

Eventually, Eight and Eleven were separated, and Kali used her abilities to run away. When Eleven met Eight/Kali years later on Stranger Things 2, she had formed something of a gang of misfits. She used her powers not only to help her friends but to take revenge on those who wronged her in the Hawkins lab.

Kali/Eight taught Eleven how to use her emotions and rage to tap into her powers on Stranger Things. She also tried to push for them to remain together as sisters and help one another heal. But Eleven was not as disillusioned with the world as Kali/Eight and did not approve of the overly violent tactics she used. So she left Kali behind to go save her friends, including Mike Wheeler and Hopper, in Hawkins. But she did draw on Kali/Eight’s advice in order to ultimately close the Upside Down gate, season’s two big issue. Eleven did that by recalling the loss of her mother and other traumas.

Bitchin’

Notably, Kali taught Eleven the term “Bitchin,” which Eleven loves to use at every available opportunity on Stranger Things. Her sister also gave her a punk rock makeover. It’s too soon to tell if the two will say “Bitchin” a lot to one another in Stranger Things 5, but we’d bet some money on it.

Kali/Eight Is the Person in Dr. Kay’s Mysterious Vault

But how does Kali/Eight come to cameo in Stranger Things 5? The government brought Dr. Kay, a fearsome military scientist, into Hawkins to study the Upside Down and help find a way to bring it down. As usual, the government does not do things gently. Dr. Kay is convinced that Eleven is, in some way, the key to the Upside Down madness, though she doesn’t know whether she is there to help or harm. Through most of Stranger Things 5, Volume 1, Dr. Kay tries to hunt Eleven down. And it’s revealed in episode three of Stranger Things 5 that the military has a sonic blast they can fire that completely neutralizes Eleven. Eleven calls it her kryptonite.

After being exposed to this weapon, Hopper and Eleven are eventually able to take down and interrogate one of Dr. Kay’s soldiers while in the Upside Down. They want to understand more about the situation, including what Dr. Kay is up to, what the military knows, and any information about Vecna. Eleven enters the soldier Akers’s mind and sees Dr. Kay pass through a secure door at her facility. At the end of the hallway is a vault door. Akers says he doesn’t know what’s behind there, but Eleven knows he doesn’t want her to see the “secret shit” inside. Akers is in agony but swears he doesn’t know what is in the vault. Eleven uses her powers to tear the door off, and Akers passes out. All Eleven ultimately understands is that someone powerful like her is behind the door.

At the time, Eleven and Hopper believe this person is how Kay learned Eleven’s Kryptonite. Eleven thinks it must be Vecna, though a skeptical Hopper says that doesn’t make sense after the vanishing of Holly Wheeler. Of course, the person behind Dr. Kay’s vault door in Stranger Things 5 is not really Vecna, but Kali/Eight. Here’s what happens.

Kali/Eight’s Stranger Things 5 Cameo, Explained

Desperate to destroy Vecna, Hopper and Eleven fight their way to the vault. But at the last minute, Hopper prevents Eleven from entering into it with him. He intends to blow himself and Vecna up to guarantee Eleven’s safety, but no explosion comes.

Instead, Hopper emerges once more and beckons Eleven into the room. And YES, there inside the vault in the secret room, the big Stranger Things 5, Volume 1 revelation and cameo arrive: it’s Eleven’s sister Eight/Kali.

Eight/Kali is hooked up to all sorts of medical equipment, and her hair is shaved as Eleven’s used to be on Stranger Things. But all we really get here is the reveal of the character and a brief exchange of the word “sister” between the pair, because that’s the last we see of Hopper, Eleven, and Eight/Kali in Stranger Things 5, Volume 1.

Doctor Kay Studied to Create Eleven’s Kryptonite in Stranger Things 5, But What Else Did She Learn?

But what ultimately is the purpose of Kali/Eight’s Stranger Things 5, Volume 1 cameo? Well, we learn that the military and Dr. Kay have been studying Kali/Eight to develop weapons that work against those with powers. As more people might end up with powers sooner rather than later (looking at you Holly Wheeler!) this could be an issue for our heroes soon. HOWEVER, if these weapons are also Kryptonite to Vecna, who shares a power source with Eleven and Eight, they could be a part of taking him down.

We don’t yet know what else Dr. Kay learned from studying Kali/Eight, but we feel it’s probably not good news if she did gain any other knowledge.

Who Plays Kali/Eight on Stranger Things?

Kali/Eight is played by Linnea Berthelsen on Stranger Things 2. Linnea Berthelsen returned to play Kali/Eight in her Stranger Things 5 cameo.

What Was the Point of Bringing Kali/Eight Back for a Cameo in Stranger Things 5?

Unanimously, fans did not enjoy the episode in which Eleven went off with Kali in Stranger Things 2. But we suppose now that Vecna appears to have given Will powers, and now that Vecna’s origin/backstory has come into sharp focus in Stranger Things 5, the story of all the number children with powers will play a major role in the narrative going forward. We guess that story does need wrapping up of some kind. Will Eight/Kali feel kinship to Vecna? (She did get her powers from his unique blood…but then so did Eleven and Will.) Or will she fight against him? Will she then become Hopper’s second adopted child? We’ll have to wait for more Stranger Things 5 to release to know for sure.

All we know for now is that the Duffer Brothers reveal that Eight/Kali will have a major role to play in the ending of Stranger Things, noting “None of it would play out the way it would if she wasn’t involved again.” And add “to really tell this story completely, we needed to bring her back. As you’ll see in Volume 2, she’s really there. Her reason for being there is very important in terms of Eleven’s journey and also the journey for this story to end.”

But, we have to say, we’d still rather have Eddie return.

Stranger Things 5, Volume 1 is now streaming on Netflix.

Rotem Rusak is Nerdist’s Editor-in-Chief. She recently rewatched all of Stranger Things in 72 hours and is still not over Eddie Munson’s death. If Steve Harrington dies in Stranger Things 5, she will cry.

Originally published on November 26, 2025.