From creator/writer Craig Mazin and director Johan Renck, the five-part HBO mini-series Chernobyl explores how the 1986 nuclear accident become one of the worst human-made catastrophes in history. After the Chernobyl Nuclear Power Plant in Ukraine, Soviet Union suffered a massive explosion that released radioactive material across Ukraine, Belarus and Russia, and as far as Scandinavia and western Europe, countless brave men and women sacrificed their own lives, both knowingly and unknowingly, in an attempt to save Europe from unimaginable disaster.

During this 1-on-1 phone interview with Collider, executive producer Craig Mazin talked about why he sees Chernobyl as a natural next step in his career, what made him want to tell this story, finding the right home at HBO, some of the most startling moments of the mini-series, juggling all of the various aspects of what happened before, during and after the events at the Chernobyl Nuclear Power Plant, and the role that truth and lies played in the outcome of it all. He also talked about the challenges of having a career as a writer, working in TV vs. working in film, and staying at HBO for his next project.

Collider: The last time we spoke was at the press day for Identity Thief, and I feel like this project could not be possibly be more different.

CRAIG MAZIN: Yes, it is different.

So, how did you get here?

MAZIN: It’s funny because it all seems perfectly consistent to me. I understand that people on the outside would look at this and go, “How does this connect?” We are multitudes, as people, and we always have an interest in things, in terms of our creatives lives, that are different, and we have different seasons and rhythms. I’m a big believer in comedy writers. I’ve always defended the honor of all comedy writers. It’s extremely difficult, but I’ve always felt that comedy writers far more easily can move toward drama than vice versa. If you look at people, like Matthew Weiner, who were working on sitcoms, and then suddenly there’s Mad Men, it’s not surprising to me. Charlie Kaufman started on The Dana Carvey Show. For me, I’ve been doing comedy for a long time, and I love it and have no regrets, but Chernobyl expresses a side of me that is far more true to who I am, on a day to day basis. It reflects my general sense of curiosity and interest in the world, in science, and in human nature. Also, as I’ve gotten older, I’ve grown more connected to the heartbreak of life. So, to me, this is the most natural thing in the world.

What was it that led to Chernobyl and made you want to write about that? Was there something that made you feel like you had to tell that specific story?

MAZIN: I was just reading casually about it, about five years ago, and it occurred to me that, while I knew Chernobyl exploded, as I think most people do, I didn’t know why, and I thought there was this inexplicable gap in my knowledge. We know why the Titanic sank. How is it possible that we don’t why Chernobyl exploded? So, I began reading about it, just out of this very dry, intellectual curiosity, and what I discovered was that, while the story of the explosion is fascinating, and we make it really clear exactly why and how it happened, what really grabbed me and held me were the incredible stories of the human beings who lived through it, and who suffered and sacrificed to save the people that they loved, to save their countrymen and to save a continent, and continued to do so, against odds that were startling and kept getting worse. I was so moved by it. It was like I had discovered a war that people just hadn’t really depicted, and I became obsessed.

Did that lack of knowledge that people had, especially of the details, help or hurt, when it came time to pitch this to networks?

MAZIN: I pitched it to one network. I only went to one place. The first person I spoke about it with was Carolyn Strauss, who is one of the executive producers, along with myself and Jane Featherstone. Then, Carolyn and I went over to HBO, which seemed like the right place to me. If anybody was going to be willing to spend a lot of money on a big program that wasn’t going to be eight seasons of blockbuster entertainment, it was going to be them. I simply told the stories. I told them how I was going to lay it out, through whose eyes we were going to experience this, what it was really about for me, and what I wanted to impart to the audience. When I was done, they said, “Thank you,” and I didn’t know what that meant. Then, the next day, I got a call and they said, “All right, let’s do it.” Every step of the way, it’s been an absolute joy. I’ve never had such a beautiful, smooth, and nourishing creative experience.

If the reaction had been different and they had said no, would you have taken this to other networks, or would you have just moved on to another project?

MAZIN: It was 2015, I believe, when I went to them, and in 2015, you might recall that there weren’t really a ton of outlets, the way there are now. There wasn’t Netflix, Hulu, Amazon and Apple, as well. In my mind, I thought, “Well, if they don’t like it, I think I’m not going to do it because then maybe there’s something wrong with me. I think this is important and beautiful, and this is a place that appreciates important and beautiful things. If they say no, maybe I’m just wrong.” They didn’t pass on it. If they had, I may have just curled up in a ball and cried for a bit, and then gone about my day.

They’re also a place that really lets stories breathe, which this story really needs to do, with the moments of silence where people are just trying to absorb what’s happened. It feels like there are lot of places that wouldn’t have allowed for that.

MAZIN: Yeah. They really let me set every aspect of this, from tempo to tone. What they bought was a six-episode miniseries, and along the way, I said, “You know what? I think it’s five episodes, and here’s why.” And they said, “Okay.” There were moments where I wanted to accelerate things and I wanted the audience to feel like they were falling because I think that’s how it must have felt to the people involved in the middle of it all. Then, there were times where I wanted to feel this long stretch of a war that you feel like you might not ever escape from. Those are things that you simply can’t do in a movie, nor can you tell a story like this from the multiple perspectives that I think it requires and deserves. So, this format was the only format I could imagine telling the story in.