The Chornobyl Nuclear Disaster

The RMBK nuclear power plant in Chornobyl exploded due to human error. After the explosion occurred, firefighters were called. One of the firefighters who came to handle the situation was Vasily. His wife worried that a chemical caused the burning, but they (especially Vasily himself) didn't know the truth, and they thought that it was just bullshit. All of the firefighters in charge were exposed to radiation and were immediately rescued and taken to the hospital. Later, the country responsible for handling the incident, which was worsening, sent Deputy Prime Minister Boris Shcherbina and Professor Valery Legasov, an inorganic chemist, to Chornobyl to manage the crisis. On the flight, Boris commands the pilot to fly over the reactor, but Legasov neglects. Finally, they stayed in a hotel. 

Later in the series, they try to bury the entire power plant in sand and boron, but one of the helicopters gets too close to the core and crashes. In the series, there’s a nuclear physicist, Ulana Khomyuk, also doing her job in handling the situation. Ulana Khomyuk asks the Soviet authorities—specifically officials within the Central Committee—to take immediate action to prevent a further explosion at the Chornobyl nuclear power plant. Still, her warnings are rejected, forcing her to travel to the site herself. She met Valery and Boris and convinced them that she is capable of helping the whole country manage the crisis, due to her will to do good. Finally, her efforts showed a little success.

Later in the series, Ulana manages to find out something by talking to some nuclear power plant workers who were present during the incident: Leonid Toptunov, a Soviet nuclear engineer and Senior Reactor Control Chief Engineer, who provided information.