Who is Kali AKA Eight in Stranger Things season 5?

Warning: Major spoilers ahead for Stranger Things season 5 episode 4.

After three years of waiting, Stranger Things season 5 is officially here, with the end of episode 4 giving us a return no one expected.

The final season of the Netflix hit catches up with our heroes, including Noah Schnapp's Will Byers and Millie Bobby Brown's Eleven, and sees a time jump at the beginning of the season, with Vecna (Jamie Campbell Bower) having been missing for months as he plots in secret.

With Eleven and adoptive father Jim Hopper (David Harbour) searching for Vecna in the Upside Down, they stumble across someone unexpected – but very familiar indeed.

Here's everything you need to know about the return of Kali AKA Eight, played by Linnea Berthelsen. Alternatively, if you want more Stranger Things, check out our review of season 5 or delve into the stellar soundtrack.

Who is Kali AKA Eight in Stranger Things season 5?

Kali AKA Eight is another of the children experimented on in Hawkins Lab, and is like a sister to Eleven. She has psychic abilities, although never developed telekinetic powers like Eleven did. Since her escape from Hawkins Lab, she has sought vengeance on those who wronged her.

Eleven and Kali would play together in the Rainbow Room at Hawkins Lab as children. Ultimately, Kali escaped, using her powers, and Eleven lost her memories of her sister when she banished One AKA Henry Creel/Vecna (Jamie Campbell Bower) to the Upside Down.

Years later, Eleven learned about Kali and tracked her down, and found that Kali was operating as part of a gang who punished those who had wronged them in the past. Kali was thrilled by Eleven's arrival, saying she felt complete now her sister had found her.

However, during a mission to hunt down Ray Carroll (one of the workers at Hawkins Lab who had tortured Kali and Eleven), the pair had a major disagreement, with Eleven stopping Kali from killing him after seeing a photo of him with his family.

Despite Kali's encouragements to stay, Eleven would then flee to find her friends, leaving Kali behind. Kali was devastated at her sister's departure, and it was safe to assume that the pair may never see each other again.

However, season 5 reveals that Dr Kay (Linda Hamilton) has been holding Kali prisoner in the Upside Down and experimenting on her, seemingly to extract her powers and transform them into technology used to inhibit Eleven's powers.

The pair see each other at the end of season 5 episode 4 and, with any luck, they'll find a way out of there together.

Ross Duffer told Deadline of Kali's return: "We’ve always wanted to bring her back because Linnea’s an incredible performer. We wanted to give her another chance to shine, but we talk about it every year, every season.

"We didn’t want to just put her in, to put her in. We wanted her to have a real impact on the narrative and on Eleven’s journey. As we hit this final season, it felt wrong to not bring her back."

The writer has also promised that Kali will fit neatly into the narrative of the upcoming episodes, adding: "As you get into the second volume, you really see how she fits into the narrative and Eleven’s journey, and she plays a really important role moving forward."

Who plays Kali AKA Eight in Stranger Things season 5?

Kali is played by actress Linnea Berthelsen.

Outside of Stranger Things, Berthelsen has appeared in various short films and TV series, including Teenland, What Tyler Did and Devs.

During an interview with Coveteur in 2017, Berthelsen opened up about that final moment between Eleven and Kali in season 2, which saw Kali gazing sadly out of a car window, left heartbroken by her sister's departure.

She said at the time: "It’s really interesting because people get different things from that moment. It’s very challenging – this is something [Kali’s] never seen before. She’s never tried to feel this way.

"I would guess she’s just lost and very confused. I feel like I shouldn’t explain that moment, because it’s very unique that everybody has their own interpretation."

Who could have predicted she'd be back for one last adventure?

Stranger Things season 5 volume 1 is available on Netflix now. Further episodes follow on Christmas Day and New Year's Eve. Sign up for Netflix from £5.99 a month. Netflix is also available on Sky Glass and Virgin TV.

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