Two scenes in "Chernobyl" reveal the genius of Mazin's process: matching clear intentional writing with masterful acting and mise-en-scene.

Craig Mazin is a workaholic who has not faced one day since 1995 without some kind of deadline. Pegged early on as a Hollywood comedy screenwriter, he weathered two “Scary Movie” and two “Hangover” sequels. So it was something of a surprise when he created riveting true-life drama “Chernobyl,” which became not only HBO’s most successful limited series since “Band of Brothers,” but scored 19 Emmy nominations, beat only by “The Marvelous Mrs. Maisel” and “Game of Thrones.”

Apart from his own output, Mazin built a reputation as a writer partly via the popular Script Notes podcast. Back in 2011, fellow writer/blogger John August invited his colleague to join him on a new podcast; they have delivered it every Tuesday ever since, free of commercial interruption. Podcast producer August is “the classic WASP-y not straight straight guy,” said Mazin in an interview at his Pasadena office. “I’m the goofy guy, the yelly Jew.”

It works. The podcast has built a huge Hollywood following, elevating both men within the ranks of the Writers Guild of America, West, where August currently serves on the board of directors. Mazin was also recently urged to run for office, but withdrew his bid for family reasons.

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In the past decade, Mazin found that many of even his most acclaimed writer friends were asking for his notes on their work – including dramas. The podcast reveals why: Mazin has an analytical ability to deconstruct just about anything. Eventually he asked, “What is this faith in me I don’t have in myself?”

Gradually, Mazin turned down more assignments and gave himself permission to dabble in more personal material. Five years ago he became obsessed with researching the nuclear power plant explosion at Chernobyl: the documentaries, the online videos, the books like oral history “Voices from Chernobyl.”

He saw the miniseries unfold in his mind. He showed a pitch to his “Game of Thrones” pals David Benioff and Dan Weiss: “Is this a show?” “We think it’s a show.” He also asked their executive producer Carolyn Strauss. “Yes.” She took him to HBO, which gave him development money for a bible and a pilot. “I knew exactly how to do it, I could see it,” Mazin said. “Structure, what the perspective should be, the variations of the story.” His one mistake: the show unfolded in five episodes, not six.

Liam Daniel/HBO

Mazin understood there was ongoing interest in Chernobyl because the Soviets had withheld so much information. “We didn’t know things,” he said. “It needed to be brought up because part of the theme of the show is that truth matters.” That’s why he insisted before making the series that there be an accompanying podcast transparently explaining how he arrived at his fictional reality. “I can’t do this and not be accountable and explain the changes we made…There are so many things about ‘Chernobyl’ that are true and hard to believe.”

Mazin wrote the series with his three top actors in mind: Jared Harris as nuclear physicist Valery Legasov, because “he seems legitimate as an actual real-life scientist, who felt appropriate for the space, and felt very internal,” he said.

He was thrilled to reunite for the first time “Breaking the Waves” costars Emily Watson and Stellan Skarsgård, as the composite characters of a nuclear expert and apparatchik, respectively. “Part of why ‘Chernobyl’ works as it does is it was written for them,” he said. “When casting happens, things get broken. When you write for somebody and don’t get them, there’s a strange realignment. You go and readjust, but it’s never quite the same.”

After plenty of production experience as an on-set writer and problem-solver, from casting to the editing room – “you are the unauthorized parent at a certain level in features” – and having directed two low-budget comedies, Mazin was confident he could showrun a limited series. “In television creatively, more than a lot of movies where the directors are important,” he said, “screenwriters are important.”

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What he needed was the right director to shoot every episode. This was his “most nerve-wracking” decision. “I do not want a big feature director used to being in charge,” he said. “I want someone who will do things I would ever dream of doing, deliver a beauty I cannot. I also need them to do what I want and follow the vision of the show. Their beautiful thing that I can’t do should be compatible with the thing I can.”

Mazin was most impressed by Swedish commercial helmer Johan Renck, who had directed Madonna and David Bowie videos as well as episodes of “Bloodline,” “Breaking Bad” and “Better Call Saul,” as well as Channel 4’s Balkan War miniseries “The Last Panthers.” Mazin was especially struck by a Swedish thriller not on Renck’s official resume. “It was so beautifully done, with a bleakness and hyperrealism so real it wasn’t real,” he said. “His fingerprint was so specific. He was doing the things I know I can’t do.”

As a screenwriter used to being replaced at will in movies, Mazin loved being in charge, and sharing his anxious authority with his three trusted collaborators, Strauss, Renck and producer Jane Featherstone. “It was important to me to work with people who were kind and nurturing and supportive of each other,” he said. “No days of being vindictive and sniping. I was treated the way I’d always wanted to be treated.”

Liam Daniel/HBO

Two scenes in “Chernobyl” reveal the genius of Mazin’s process: matching clear intentional writing with masterful acting and mise-en-scène. Unlike most writing teachers who preach dialogue as the main screenwriter’s tool, Mazin writes thinking into his text.

In his “Chernobyl” script, he builds up to the moment in Episode 2 when the scientist Legasov realizes how bad the nuclear explosion really is. The camera holds on his face as he reads the initial report. When he goes into the big conference room meeting led by Premier Gorbachev, Legasov is anxious to know what everyone else knows. “I tried hard to maintain internality,” said Mazin. “I wanted everything processed by people’s reactions.” So in the script, Legasov goes in, sees what’s happening, and in italics, Mazin writes what he is thinking: “Please let someone else say it, anyone else but me, they don’t know!” That’s exactly what Harris shows us in the scene – which is a lot more precise than the usual screenwriter direction: “(anxious)”.

Liam Daniel/HBO

The second pivotal scene is the one that makes viewers yell at the screen. (I screamed, “You’re dead! You’re dead!”) Mazin has carefully built up to the rooftop scene. Days after the Chernobyl nuclear catastrophe, the Russians are trying to figure out how to cover and put out the still-burning fire at the crater of the explosion that has melted the core of the power plant. We know helicopters are destroyed if they fly over the crater site. The engineers need to push all the radioactive debris off the roof and into the crater. Even a high-tech German robot vehicle couldn’t sustain exposure to the radiation, which was clearly far greater than they had figured. So they have to send in bio-robots: human soldiers in “protective” suits will rush across the roof for 90 seconds at a time and hurl away the radioactive material.

“Everything about that is factual,” said Mazin, who knew that narratively, “this was a right hook you can throw.” (For his pals Benioff and Weiss, the right hook for “Game of Thrones” was the Season 3 Red Wedding.) “We would have earned the audience’s attention, and could ask them to look at something for 90 seconds that doesn’t cut.”

He and Renck carefully choreographed the shot on a hot day in Lithuania, from the point of view of one soldier crossing the roof, throwing off rocks, and returning. “It’s a oner,” said Mazin. “The camera or guy moves the wrong way, the thing falls off the shovel the wrong way, the 90-second take is no good. We used the eighth take. We probably did it nine times.”

Mazin has learned the hard way in comedy that what you think is hysterical will bomb, and minutes later “the dumbest joke in the world destroys.” While they showed the series to HBO and screened the first two episodes at BAFTA, Episode 4 went straight to audiences, and Mazin watched it at home like everyone else. “Tonight’s the night we lose them,” he’d say. Twelve million people watched the show.

HBO

The thing that matters most to Mazin is that “Chernobyl” has made a difference in the world, whether it’s Ukraine liquidators finally getting the credit they deserve or the rise in tourism in a poor country. Mazin uses his Twitter account to fight for climate change. “When we grew up we learned that the Soviets were not like us,” he said. “Everything about their system was so oppositional to ours. We would never behave as they behave. They didn’t do anything we weren’t capable of doing. And we are now doing things similar to what they do. We are acting in firm denial of something we don’t want to be true. The nuclear reactor was the one thing they could not control. Our climate doesn’t give a shit, heat melts ice, that’s how it works. That we are still engaging in climate change debate is remarkable. Most of us get it. It’s just bizarre to me: there’s no political advantage to getting hot.”

When Mazin finally visited Pripyat and Chernobyl right before shooting, nature had taken over what is now one of our largest wildlife preserves. “This world, were it not for us, belongs to bugs,” said Mazin. “There were insects everywhere. In one summer retreat area near Pripyat, a creepy, dilapidated dormitory had vibrating walls infested with bees. The part that fascinated us the most was this ghost city, what Chernobyl now is. It is a symbol of our mortality as a species. This is what happens when we are gone.”

Next up: Mazin is developing a few series for HBO. One is a dramatization, this time of a recent true event in the U.S. that “we do not know about, but need to,” he said. Another is based on an allegorical fictional story he has loved for years. And another close to his heart (and experience) portrays kids with mental health issues and their parents. “I’m obsessed with showing things for real,” he said. “It can be heartbreaking and funny and real.”

Final-round Emmy voting is open from Thursday, Aug. 15 through Thursday, Aug. 29 at 10 p.m. PT. Winners for the 71st Primetime Emmys Creative Arts Awards will be announced the weekend of Sept. 14 and 15, with the Primetime Emmys ceremony broadcast live on Fox on Sunday, Sept. 22.

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