For those who’ve seen the second season of Netflix's Stranger Things—shield your eyes from the below spoilers if you haven’t—there was one episode that was undoubtedly the most talked about. It was centered around Eleven's personal journey outside of Hawkins, where she hopped on a bus to Chicago and had her first brush with punk—an ‘80s touchstone heretofore unexplored by creators the Duffer brothers—as she got to know her rough-and-tumble “sister” from Hawkins Lab, number Eight, also known as Kali. While Eleven, or Jane, had been preoccupied with the Mind Flayer’s army of Demogorgons, Eggos, and her budding romance with Mike Wheeler in Indiana, Kali had been living an entirely different existence, using her reality-altering powers to seek revenge on all those who’ve wronged her and her merry band of pranksters. After a taste of that lifestyle, however, Eleven ultimately rejected it to reunite with her adopted family in Hawkins, saving them from the Mind Flayer along with the rest of humanity. All in a day’s work for a 13-year-old.

Maybe it's fan's obsession with Eleven's original storyline in a show as dense as Stranger Things that made episode seven feel extraneous and out of sync for some viewers. But for young Danish actress Linnea Berthelsen, who played Kali, the pivot was a brave, experimental move. “I loved the episode and I loved the characters and I trust the Duffers,” Berthelsen explained this week. Regardless of whether or not the episode was needed, it certainly added to Eleven’s character development and stylistic evolution; there's plenty to love in Eleven’s punk look. Here, Berthelsen explains how the storyline came about, how the cast passed the time between takes, and whether or not a Kali spin-off is in the works.

Berthelsen as Eight and Millie Bobby Brown as Eleven.

Courtesy Netflix

How has life been for you since the release of the second season?

Really good. I’m relaxed and home in Copenhagen.

Were you a fan of the show before season two?

So I didn’t see the whole show until I did the audition, but I became a fan straight after watching it.

What was the audition process like?

It wasn’t easy. I got in on Friday afternoon, I had to watch the show, I got three different scenes and I got the breakdown of my lines. So I had to create the character and make it a real person from these scenes and the breakdown, and I could only spend Saturday preparing for it and then film it on Sunday. It’s the most intense thing I’ve ever done, but it was fun.

Do you think it’s a show that’s made to be binge-watched?

Yeah. I feel like it was really great to try it for once and binge something for nine hours. I loved the show and the characters.

It seems like the cast is so tight-knit. What was it like stepping into their world in the second season?

It was really cool because everybody was really excited to be doing the second season. Obviously, we created a new world for this episode I’m in, so I had a new crew and new cast, but we still had people who knew what they were doing. The filmmakers and the showrunner had been on season one as well so it was a good mix.

What’s your favorite memory from being on set?

I spent a lot of time with the gang and Millie [Bobby Brown], and I remember during coffee breaks sometimes Millie was like, "Okay, I want to go out and play." So we went out to play baseball three or four times in costume. I was wearing heels. But we were like, "We need to do this. It’s all for Millie."

That’s really sweet. When Millie had her makeover, did you actually help with it?

Yeah, we put the makeup on her in the episode and found outfits.

Did you personally come up with the direction for her look and your own?

My outfit was pretty amazing. I Skyped with the costume designer Kim Wilcox a few weeks before I got on set and she asked me, "What do you think for this character? This is what I think." When I showed up on set, she had maybe 30 different outfits, jackets, and pants, and she wanted me to try a lot of things and see what I liked. I picked my favorite costume I felt comfortable in and the showrunner and the Duffers had to approve it, but it became the final outfit.

Millie had the same conversation with Kim but I remember she came to the trailer to show me the outfit and she was so excited about it. She was like, "Yeah, I’m the baddest." She was really excited about the episode. It was really cute.

How did you get into the mindset of having supernatural powers?

To be honest, I didn’t focus on her having super powers because Kali is really human. She has her weaknesses. So I treated her as a human being who’s been traumatized. I did a little research in the background and filled out the gaps as to how she became like this, what happened to her, and why she can’t connect with other people.

Why is Kali so much more hardened than Eleven?

She’s older. She’s been through a lot since she left the Lab. She’s had more years of having to deal with homelessness, abuse, god knows what. So she’s had to learn from that and that’s why she has such a hard time connecting with other people: They can’t really relate to her. She has to find her own way of dealing with stuff.

Eleven ultimately turned down her lifestyle. Do you think that Kali would ever do the same?

No. [Laughs.] I think that was very life-changing for her when Eleven left—not necessarily because she disagreed or was angry. She really cares for Jane and she thought she was doing the right thing. And then she realized that she didn’t, and it matters to her.

So you think Kali realized she wasn’t doing the right thing?

Oh yeah. It was the first time she realizes that she’s not right, that she can be wrong as well.

Do you think her character would ever reject that life and go to Hawkins to be a family with Jane?

[Laughs.] At the end of the day, that is a Duffer brothers question. But I hope so. We’ll see.

The Duffer brothers called episode seven “a whole little other pilot episode in the middle of your season.” Are there any plans to make a Kali spin-off?

No, I don’t think so.

Were you given any information about Kali and Jane’s other siblings? Executive producer Shawn Levy has said that there are more out there.

In order to fill in the gaps, I needed to create a world that I believed in so I did this based on the things I talked to the Duffer brothers about. But nothing is decided. We’ll see what the Duffers are going to make up.

Episode seven was kind of a controversial one. What were your feelings about the way the episode was received?

I haven’t really focused on that because it’s not my storyline, it’s the Duffers and, at the end of the day, I’m a big fan of their work. I admire them so much that they’re taking risks and I think it’s really brave.

If you had Kali’s powers in real life, how would you use them?

Maybe sometimes when I feel like I’m really awkward in a situation, I would make myself disappear. Or, if I’m at a party and I feel awkward, I would use my powers to make myself look pretty and give myself a pretty dress.

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