Jamie Campbell Bower breaks silence on top-secret Stranger Things role in season 4

Warning: This article contains spoilers for Stranger Things season 4.

Jamie Campbell Bower wants to apologize to fans of Stranger Things.

When Netflix announced him among the cast of season 4, he was named in the series regular role of Peter Ballard. The character came with a vague description: "A caring man who works as an orderly at a psychiatric hospital. Tired of the brutality he witnesses day after day, will Peter finally take a stand?"

"I have no idea where the name Peter Ballard came from," Campbell tells EW in one of his first interviews since landing a part on the drama. "I can only apologize to fans of the show for being part of such a massive red herring. I remember seeing it and being like, 'Okay, guys. Cheers! That's going to be a tough one if anybody asks me, but I'll just go with the party line.'"

The Twilight and Mortal Instruments star hasn't been able to talk about his real role for quite some time, but — after being listed as "Friendly Orderly" in the episode credits — it was finally revealed in the finale of season 4, Volume I. The actor plays One, the very first kid with psychic powers that inspires Dr. Martin Brenner (Matthew Modine) to launch the program that gave us Eleven (Millie Bobby Brown).

Born Henry Creel, One first used his extraordinary abilities to terrorize his family before he ended up at Brenner's facility. At some point when he got older, the doctor known as "Papa" implanted a device in the boy's neck to suppress his powers and force him to work as an orderly at the lab. But when One manipulates Eleven into removing it, he unleashes his telekinetic wrath, killing nearly everyone. Eleven, however, is able to overpower him. In doing so, she inadvertently breaks open a portal to the Upside Down, where One has been trapped for years — a traumatic memory Eleven had blocked out. In the present, One now goes by Vecna, the demo-creature using his psychic powers to possess and kill teens in Hawkins.

Campbell finally opens up about playing Henry/One/Vecna. And, yes, that is him wearing the Vecna prosthetics and making that deep Vecna voice.

ENTERTAINMENT WEEKLY: I know everyone involved with Stranger Things typically likes to keep secrets close to the vest. I'm curious how much about this character you knew going into the audition.

JAMIE CAMPBELL BOWER: I knew nothing. They sent me two sets of sides, originally. One was from Primal Fear and the other one was from Hellraiser. Then for the recall, they sent me some dummy sides from the show, at which point there was a little bit more information about the character, but not loads. [The scene] was actually what ended up being the Chrissy kill. Then I was in L.A. and I just went mad. I did one of those detective mind map things and put Will Byers in the middle and then all the other characters and what I thought was right, inspiration wise. Then I was called into a meeting with Matt and Ross Duffer, and I took a little folder that I had of all these images. I was pretty quiet during the meeting. It was one of those things where it was like, "Keep your f---ing mouth closed and everything will be fine." After we had a getting-to-know-one-another conversation, I was like, "Look, I have this book of what I think this character is. Do you mind if I show you?" I showed them the book and they were like, "Have you read the script? This is literally perfect." So, they scuttled off into the backroom of the house that they write in and came back with all these amazing 3D renders and telling me more about the story of Vecna and of Henry and of One. It was mind-blowing. The way I always saw this journey for Henry was: sweet, sweet, sweet, nice, nice, nice, manipulate, manipulate, turn, full on total resentment, hatred, carnage.

That's interesting about Primal Fear and Hellraiser. Did you take a lot of influences from those two works into this performance?

Primal Fear, less so. Hellraiser, I love. I love Clive Barker. To my utter shame, I love all the Hellraisers. Three, I think is probably my favorite, but that's the great thing about working with Matt and Ross. Their references are so beautiful and so brilliant and are the things that I love. I was like, "Yeah, Hellraiser, I'll take a bit of that, a little bit of Freddy [Krueger]." But not too much Freddy, because the way Robert [Englund] played Freddy, there was a chaotic energy. With Vecna, I saw this resentment, this really built-up anger. You know when you get so angry, you start shaking you're trying to hold it together? That's what I took. For Henry, I actually drew on more real aspects: what I could draw from myself and from people that I knew. It was all about him being the outsider and the recluse and not being accepted and seeing the lies that his parents told, and the world is a lie. I started at the end and then had to track back and think. That's how he really feels, but what has his experience been and how does he manipulate Eleven and his environment enough to be able to get what he wants? The sweetness was a very jarring process to attach to all this burning fury that's inside.

When your casting was first announced, you were linked to a character called Peter Ballard and it had this very vague character description. Do you know where that name came from?

I have no idea where the name Peter Ballard came from. I can only apologize to fans of the show for being part of such a massive red herring. I remember seeing it and being like, "Okay, guys. Cheers! That's going to be a tough one if anybody asks me, but I'll just go with the party line."

Is it you under the prosthetics of Vecna and also doing the voice?

Yeah, that's me doing the voice under the prosthetics. It's all me. Ninety percent is practical. The only thing that is not practical are the vines moving on the neck. The voice was an interesting thing. It took me a minute to get that. I'd done so much work on Henry and One before the read-through. I knew how Vecna felt, but I hadn't quite got the voice yet. I would send Matt and Ross audio recordings of myself with spooky vampire music underneath it as this voice was progressing. I've got countless videos on my computer of me doing it... well, doing it badly, walking around pretty much naked. It was funny. I was in ADR for the show a couple of weeks ago and the engineer was like, "I've got this octave [voice distorter] for you." I was like, "Oh no, we don't use that." He was like, "What do you mean?" And I was like, "It's all me." He was like, "Yeah, whatever. Go on." And so I did it and he was like, "Right. Yep. I've canceled the octave of that. It's off now." But it was hard as we were filming. Because the suit comes over the ears and the ear holes are very, very tiny, to be able to fully hear myself was quite difficult at the time. I was feeling it, but there's always that wing and a prayer where you're going, "I think it's good. I hope this is coming across well."

How did just wearing the prosthetics shape your physical performance as Vecna?

The physical element of Vecna came beforehand. I knew I was going to have this incredibly long hand. I would spend hours looking at my hand, imagining my fingers extending further out, and playing with that a lot. There's a certain stillness to him. Everything's very methodical. I would spend time walking around downtown Los Angeles or going for a hike, just feeling this out. There was another really interesting thing that came as we were filming, too. It came from within. It was like I had to push the energy out of my body so I was really filling the space, presence-wise. I remember walking onto set as they were building Vecna's mind lair and looking at the size of it going, "Holy f---, this is huge! I really need to own this space 100 percent." Then when the costume was on, it was about applying those sensitivities that I created in my mind. The hand is this amazing thing that has all these metal wires in it, so the fingers become quite dextrous. Then on a practical level, there's the weight of the thing. It weighs about 35-40 pounds, which is not loads, but when you're wearing it for 10 hours and the predominant weight is on the shoulders and on the head, how do you make sure you're not falling over? There's that Kubrickian stare that I wanted to bring into it, as well.

There's still so much we don't really know about Henry's evolution into Vecna. We don't really know how he went from being a lab rat to being an orderly. How much of that backstory do you know, or did you even want to know coming into this?

I knew and assumed a lot going into it. It was important that I had that in there, that I wasn't just finding him in the same way that the audience was finding him. I needed to know how bad Brenner was working with him and why he had this suppressor put into the back of his neck. I needed to know all of that in order to be able to track the story.

We also have two more episodes that we're going to get later this year in Volume II. By all signs, it seems like it's setting up for a rematch between One and Eleven. How would you describe these final two episodes compared to what people see in Volume I?

I'm going to toe the party line here. It gets bigger. If you thought that it was as big as it could get, it's not. It goes further, visually, story-wise, and emotionally for all the characters. It really is quite an explosive climax, let's say. I know lots of people have used the word explosive and scope and scale, but I do mean that. It goes a lot further and we get to know more as well. We learn a lot more as an audience in these final two episodes, as well.

Does that include more of Henry's backstory?

I couldn't possibly say. I feel like a politician sometimes. You get to know more about all the characters.

This will probably result with the same kind of response, but we know season 5 will be the final season. Have you had any conversations about returning for that?

I have had conversations about where the show goes in season 5. I couldn't possibly give any spoilers or tell you anything at all, but I know a bit.

Stranger Things season 4, Volume I is currently streaming on Netflix. (Read our full recap.) Volume II is set to premiere on July 1.

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