Summary 1978. In the laboratory of the Thermonuclear Fusion Institute in Warsaw, the team of general Grzegorz Giedrowicz and professor Teresa Titko conducts a successful experiment of thermonuclear fusion. General Giedrowicz immediately calls the first secretary of the Central Committee of the Polish United Workers' Party, Edward Gierek, and reports on the great success of Polish physicists. Satisfied, Gierek and Prime Minister Piotr Jaroszewicz are planning the next step - a trial thermonuclear explosion. 2010. Kornelia Titko receives a strange letter, addressed to her long-deceased mother, Professor Teresa Titko. The sender of the letter, who introduces himself as a forester, Stanislaw Wanio from Swietoszyn, claims that he knows why Kornelia's older sister and Teresa's second daughter, Jagoda, died. In a letter, he warns Teresa that she is in great danger. Surprised Kornelia calls the sender of the letter. A man, hearing that Professor Teresa Titko has been dead for many years, throws the receiver, opens the gas in the stove and lights a cigarette. Kornelia talks with her son Marcin about her sister's past death. Marcin makes her realize that he knows nothing about her. At the same time, a man burned in a gas explosion is brought to the hospital .

• Crime
• Drama
• Mystery