Stranger Things type TV Show network Netflix

Warning: This article contains spoilers for Stranger Things season 3.

Well, at least we got to see lifeguard Billy and those red trunks.

But otherwise the bad boy, played by Dacre Montgomery, spent the majority of Stranger Things season 3 possessed by the Mind Flayer and basically turning a good portion of Hawkins into zombie blob people. After doing A LOT of bad stuff, Billy sorta redeemed himself by battling the Mind Flayer on behalf of Eleven (Millie Bobby Brown). Alas, the mullet lover did not survive, and died with half-sister Max (Sadie Sink) by his side.

Stranger Things creators Matt and Ross Duffer originally planned to have season 2 end with Billy being possessed, but then decided it would be better for ST3. “It’s been an idea that’s been there for a while,” Ross tells EW. “Dacre’s known about it. We’ve all known about it. It’s one of those sort of big ideas that when we first stepped into the room to discuss season 3, that was one of the first things that was put up onto the board.”

Montgomery, who joined the series in season 2, talked to EW about this huge arc for Billy and saying goodbye to that mullet.

ENTERTAINMENT WEEKLY: When did you first know that Billy was going to be this season’s big bad?

DACRE MONTGOMERY: It was spoken about a lot in season 2, about where the arc would go. Now, I didn’t know specifically it was going to turn into what it turned into. But I knew that it was going to get really dark. I knew that he was going to be the leader, in many senses, of darkness in the second season, but I didn’t know how it turned out. What [the Duffers and I] did discuss, however, was the biological-mother components. That was something I actually brought to them about two or three months before they started writing season 3. I had written a whole backstory, and this just speaks words to them because they’re super-collaborative.

We jumped on the Skype session and I had written this whole backstory because I was like, “I want to hear about my biological mother.” So I wanted to know like, where did he come from? Because we never spoke about that in season 2. That’s why she reaches into my memory. You’ve obviously seen in it at the end, in that pivotal scene for all of the characters, including my own and directly with Eleven. That’s why that’s there. And I think that’s what I didn’t expect, to answer your question.

You basically have to play two very different Billys this year. What was that like to get to play as an actor?

I think it’s either the opening credits scene or the end credits scene in episode 2 where I meet the other Billy. I come out of the phone booth and then the dark force comes. That was amazing. I mean, I’ve never done a scene with myself. The reason I’m bringing that up is because I think that is truly the best example to answer your question. That was actually a scene on an evening where I play myself and I play Flayed Billy in the same scene, within the same hour of shooting. That was interesting. Look, I was very aware of these zombie-like things that some people might do in this situation when it involves possession or being controlled or any of those sort of things; I really wanted to stray away from that. So all of the eye contact that I have from that point as Flayed Billy pretending to be real Billy is so powerful.

That’s why when you see at the end I meet Eleven in the Upside Down in the cabin, I walk towards her and I’m like, “Here’s what we’re going to do, here’s how we’re going to do it. We’re going to find you, we’re going to kill you with…” blah, blah, blah. The reason at the end of that speech, I am so emotional, right? I’m crying because that is supposed to be Billy in [my] eyes that you see, and what the audience is seeing is Flayed Billy, but I tried to play in my eyes, fighting really hard to get through that veil or wall or whatever you want to call it.

You have to do a lot of stunt work in this, including being levitated. How intense was that aspect?

That sauna scene [in episode 4] took five days to shoot, and I put every blood, sweat, and tear that I have into it. I have photos from the final day when I left set and I got all of my prosthetics, my wig, my makeup, everything taken off and my body is covered in bruises and cuts, head to toe, because I absolutely did everything that I could. I peeled all the skin off the top of my toes in real life from dragging myself across the tile floor. I helped bring all these crazy ideas to Shawn Levy, who directs that episode. I’m being completely honest with you here that I put everything that I could into this season.

You’re also separate from a lot of the cast this season. Did that help in playing the darker aspects?

I think it helped play to the darker side of it, and the great thing was that when I did get to play with another character it was Millie. Her emotional maturity is incredible when she just commits, and I like to think of myself as an actor that gives 150 percent every second that I’m on set. So to meet another actor who I hadn’t worked with before, because Billy and her meet for the first time, was really rewarding because then you finally meet the counterpart, where you’re like, “She is going to give every blood, sweat, and tear that she’s got. I want her to know that I’m going to give everything else.”

Speaking of Millie, she’s there for your death scene, which is a huge sequence. What was that like to shoot?

We shot that over three days. Yeah, it’s huge. I lost my voice every day we shot. In between each take, Millie and I would just scream at each other — scream, scream, scream until the camera rolls. We both start crying, and most of the time it was night shoots. I just tried to be there with her and it was emotional, you know, we cried.

Are you sad to see the wig go?

The wig, yes. A big part of me. No. I think I am in some respects, and some, you know, some respects I’m not.

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