Starz’s new original series Counterpart gives J.K. Simmons the role of a lifetime. Well, at least by sheer volume – playing a double role gives him twice as much material. Simmons plays Howard, a regular joe working a desk job, who one day meets himself. The other Howard comes from a parallel world that was just discovered,and he’s a badass spy. Normally regulated so that counterparts never meet, the spy Howard needs to involve the original Howard, which raises many questions for the Howard finding out about this for the first time.

/Film spoke with series creator Justin Marks after Starz’s panels for the Television Critics Association. The screenwriter of The Jungle Book, its upcoming sequel, and Top Gun: Maverick, Marks told the TCA that he had a 100 page bible of how the parallel worlds work that read like stereo instructions. He shared more details with us in our one-on-one interview.

What came first? The two Howards, or the concept and then you created the characters in it?

I would say the concept. Counterpart started off of the question, I started to wonder very early, that Sliding Doors question that we all ask ourselves one time or another. Who would I be under a different set of circumstances? Would I be happy? More fulfilled? Less fulfilled? Would this person be a good person or kind of a jerk? We’ve all wondered that. We’ve all had those questions. What I felt like I had never seen and what I began to be really curious about is what if I could meet that person? What would that person be like and would I like him or dislike him? Would he like me? What if we really hated each other? How would that play out? What if we began to covet what the other had and want to slowly work our way into that other’s life and maybe steal it from each other? Then you think of the espionage genre which I grew up on, whether it be Graham Greene or John LeCarre, the British spy fiction that I love, it’s all about secrets and people with secrets. How would that work in a world where you’re working against an operative who knows all of your deepest, darkest secrets because that person shared your life until a certain point?

How do you refer to each Howard in the script and on set?

That’s an easy one. The rule on Counterpart is the first character you meet is just their name, is just Howard. The second character you meet, if they’re from the other side, they become Howard Prime, which is Prime as we call him very simply. If they’re from our side, they’re Alpha. Alpha and Prime is how we do it.

Do the Howards become more alike as this series goes on?

That’s sort of the territory the show likes to explore. This idea that I believe no matter what circumstances are, there is one true self somewhere buried at the center of all of us. If you stripped nurture away, you would find it at that nature. The question is what is that true self? Is it more like Prime or is it more like nice Howard? As it goes on, I think we’re going to be surprised where that middle is because they will start to find each other near the middle. That middle might be a more dangerous place than we otherwise expected.

How much of the 100 page bible will never even make it onto the show?

Probably a lot of it because even in the first episode, as they come through the set we call Customs, where you clear the crossing and you first come into another world, you see these guards stamping these visas in very specific places, just because the actors who played them have all read the stereo instructions. They know exactly what stamp goes where, what shape, color it should be, because we had to build and design it. What I love, especially in science-fiction, I love the movies and TV shows that give you a huge world, they’ve built a complete world down to the smallest detail and then they turn off the overhead lights and they they just give you a flashlight and they just let you pan around it. I think there it’s more about the details and it’s less about “look at all the ideas we have.” I just want people to trust us when they see those guards stamping or when they see the different number protocols or the binders on the walls, that we put the thought and attention into those details so the actors can know what it is and so it can feel real. The worst thing you can do in science-fiction is something that doesn’t feel lived in, that doesn’t feel detailed in the way that has its own verisimilitude.

Are you dealing with characters who don’t know the science of it, so you can just tell the story and not be bogged down in the science of it?

The science being the existence of a crossing, yeah. Howard to a certain extent is that character until he discovers the existence of the crossing on the other side.

Howard Prime still doesn’t know how it works. He just does it.

Very few people know and Howard Prime says it in the second episode. The origin of the crossing, for example, what it was, we know as writers. There’s an episode where we get to explore it coming soon.

Which episode is that?

The second season, which is what we’re writing right now. Now, you’re going to understand some key things about it in the first season, but even Howard Prime says, “Maybe some people know but they ain’t telling.” The idea is there’s a madness at the center of it that if we understand too much, you’re going to drive yourself insane. So most of the characters go with the idea of, “You know what? I walk through that doorway and I’ll be in another world.” I’m just going to accept it and move on.” That’s one of the things that was most important to it.

I’m glad because I’m always frustrated when shows spend so much time explaining their premise that they forget to explore the drama.

Yeah, never answer a question before it’s asked. That’s my main thing. Here’s my one criteria for any movie, television show that I watch. Does it need to make sense? Does it do all this? Whatever it is, the only thing I really care about before anything else is do I care? Do I care about these characters? Do I care about the outcome of this story? I think a lot of stuff, maybe it explains the world in great detail, but I just don’t care what’s going on and I disengage. By the way, I’m a big video game player and that for me is also a very important thing. Games where I actually care about what’s happening and I’m not just skipping the cut scenes, those are the ones that I actually dig into. Everything else, it’s like don’t show me the nice wallpaper. Show me the person who’s standing there who I empathize with. That’s what you want more than anything.

What is different from our world in Prime?

We did our deep dive because in order to ignore some of the details beneath the surface, you actually have to create them. You have to build the engine before you put the hood over it so to speak. One of the things that we began to brainstorm and research was if there were a pandemic in our world in present day, how would things begin to manifest themselves? The other side, in the fourth episode, you see their medical technology is actually quite advanced and really wonderful, but smartphones, just typical electronics, are not as advanced as ours. One world is not better or worse than the other. They just progress in this different way. I don’t think we’ve ever gotten to see these alternate presents that technologically are not better or worse. They’re just different.

What are some other differences?

Some of the differences we see are architecturally. You veer towards this high contemporary postmodern architecture in the skyline of Berlin.

The corkscrew building?

Yup, I call it the corkscrew to our visual effects department. “Give me that corkscrew right there” is always the thing they hear from me. The other, we call it the arch. I don’t want to get into too many spoilers, but the Memorial Arch for the victims of the flu which is this triangular thing that sits there. Well, it’s not a spoiler. Actually that’s what I kind of like about this show. At no point does the show actually address the fact that it’s a Memorial Arch. It goes back to one of my favorite things in Return of the Jedi, the Rancor master. It was this seminal moment for me as a kid watching a genre film. You don’t just have the Rancor, you’ve got his master. When the Rancor dies, the master cries for it. That’s so complete but it’s just shown as a brief moment and then you throw it away. I wanted to do things like the Memorial Arch in the skyline of Berlin and you never have a character actually point it out and say that’s a Memorial arch. We know it as creators and we let it go.

Is there an idea that our world drains the resources of any new realm we encounter?

That’s the big question. What is this war really over? When you look at the tropes of the Cold War, resource allocation and resource theft, whether those be like the great line from The Right Stuff, “Their Germans are better than our Germans.” We’re stealing German scientists from the Russians and vice versa. That’s one of the big things that we compete over between these two sides. And then we also have just resource sharing when it comes to, in the third episode, information. The other side found a petroleum deposit in the South China Sea. We don’t know where that deposit is but if they would tell us, we know it’s there in our world. We could really profit from that. It does become a zero sum game. Eventually over time it has to be and that’s where the tension resides.