Writer Craig Mazin began researching for the project in 2014, by reading books and government reports from inside and outside of the Soviet Union. Mazin also interviewed nuclear scientists to learn how a reactor works, and former Soviet citizens to gain a better idea of the culture in 1986. Furthermore, Mazin read several first-person accounts in order to bring additional authenticity to the story. He explained, "When you're reading the personal stories of people who were there — people who lived near the plant, people who worked at the plant, people who were sent to Chernobyl as part of the effort to clean it up — in those individual accounts, that's really where the story came alive".