Much like his character, Kingsley Ben-Adir went into The OA: Part II knowing pretty much nothing. The British actor, previously best known for work onstage and few British TV shows, plays a central role in the Netflix show’s second season as private investigator Karim Washington, who’s trying to track down a missing girl in San Francisco. The OA being The OA, the story isn’t actually so simple: Karim is living in a dimension slightly different from our own, and he ends up getting caught up in a mystery involving a sinister augmented-reality game. (And that’s doesn’t even get into the part involving the psychic octopus.)

Ben-Adir sent in his tape without having seen an episode of the show, but after an intense five-month shoot, it’s safe to say that he’s become fully immersed in — and enthusiastic about — its surreal workings. Vulture caught up with him over the phone to discuss bonding with co-creators Brit Marling and Zal Batmanglij, Zendaya’s surprise OA cameo, and how much he knows about the show’s larger mysteries.

You first read for the part of Karim without having actually seen The OA. What was that like? Was it mystifying?
It was one of those last-minute auditions that came through on a Saturday morning. I had a wedding on Sunday, I was traveling, and I just didn’t have much time, so I made the decision to just focus on learning the pages. It was only when they responded to the tape that I thought, “I better sit down and watch this show before I fly out to meet them.”

When you watched the first season, what really struck you and made you think it was the right show for you?
It was this scene in the hospital where Prairie didn’t recognize her parents. All the hairs on the back of my neck just stood up, and I was just like, “What the fuck is going on?”

Did you talk with Brit and Zal about how they saw Karim fitting into the larger story? He’s been characterized as a skeptic of the mystical parts of the show.
I had no idea how Karim was going to fit in, or how he was going to be received, or anything. I had to put that to the side and focus on the scenes that we were shooting, and then you just put your faith in the creators. They’ve achieved some really incredible stuff, so it worked.

One of the biggest WTF scenes, which I thought was great, is when the OA communes with the psychic octopus. What was it like filming that?
It was very tricky because there was no octopus there. It was me reacting to Zal standing a couple of feet away, doing a commentary of what this octopus is doing. It’s genuinely me going, “What the fuck is going on here?”

You know, there’s still a lot I haven’t seen. I still have to see six, seven, and eight. I’ve just taken a job in New York and I want to make sure I have the time to watch it properly, so I’m gonna finish it up this weekend.

In the octopus scene, it’s implied that Karim may be the OA’s “brother.” Do you have any sense of what that might mean?
That’s a secret of the creators. I think that’s something for you guys to think about and find out later, so I’m not going to say anything about that.

I know you haven’t seen it, but do you know that happens in the finale? How did you react to that?
It’s incredible. I remember reading it and being like, “Wow, no one is ever going to be able to imagine this.” I’m really looking forward to sitting down and watching it all in one sweep. I was so focused on Karim’s journey that I remember what happens to me and Brit, but I’m not sure how the other guys come in from the other dimensions.

The season ends in a dimension where Brit Marling and Jason Isaacs apparently exist. Do you think you exist as Kingsley in that world?
Who knows? That’s a good question. I’m going to jump on the phone to Zal later and try and find that out. I’d like to know, too.

On Instagram, Brit posted a photo of the two of you, and she wrote about how you had to film so many scenes where you were wet and very cold.
Me and Brit, we really had some days together. We were crawling through tunnels, we were underground downtown in L.A. I think Elon Musk is thinking about building his new car tunnels down there, or whatever he’s trying to do. You’re under in the water tank for a long time. We spent days jumping out of that well, and doing mouth-to-mouth resuscitation. We started in January and we finished in May, June. You film that many scenes in that period of time, you just lose track of what day is what.

The OA is built around mysteries, and it’s a pretty secretive production. Could you talk to people you knew about what you were working on?
I didn’t tell anyone what I was doing. I told my friends and family that I was just going to do pilot season. I mentioned to my girlfriend that I was filming a show because she needed to know. I mentioned to my brother. No one really knew I was doing. [When] the trailer dropped for it, my friends from back home were really surprised. They’re like, “Man, you’re like the main part in this!”

It must’ve been hard for your girlfriend when you were like, “I’m gonna be gone for five months.”
She got to come up once, but yeah. Part of the job, eh?

I’m fascinated by the augmented-reality game that Karim tries to solve with Zendaya’s character. Were you looking at anything on the phone screen in those scenes?
There was nothing on the phone. We spoke about what it’s gonna look like and what it might sound like, but you’re looking at a blank screen. And then the effects team come in and spend hours and hours and hours and so much money trying to make everything look seamless. Karim’s genuinely baffled by it, so it felt fine to be baffled by it and not be able to work it out.

I was a surprise to see Zendaya show up. Do you know how she ended up as a part of it? Is she just a fan of the show?
Yeah, she’s a big fan of the show. I think her dad is a big fan of the show as well and she didn’t tell him. She wanted it to be a surprise for him, I remember her saying. She’s super-fun to work with.

I’m not asking you to reveal anything, but I know that Brit and Zal have talked about a five-season plan for the show. How much of that have they shared with like you?
I think they wanna keep it as much as a mystery as possible for everyone. It’s probably best for everyone — me included — to not know. Actors wanna know everything, and I think having shot the second season, I could have known a lot less in a way that may have been helpful. I trust Zal and Brit. They know what they’re doing and they plotted this thing out. I hope for them and I hope for everyone that they get to do their five seasons.

With these American shows, no matter who you are or what your part is, they try and sign you up for the whole thing. So, in a way, I’m signed up, but who knows what I mean?