An artistic drama about the tragedy of the city of Pripyat. The most terrifying catastrophe in human history. The powerlessness of the authorities, the disbelief of ordinary citizens, inexperience and negligence - all these are the details of one fateful Saturday night. Physicist Ulana Khomyuk decides to investigate the causes of the explosion, but in the Soviet state, it is practically impossible to do so. She seeks help from Valery Legasov and Boris Shcherbina, who, despite their social status, also face such problems.