One day in the life of a simple Soviet family. Spouses Stepanov's on that day decided to terminate the marriage, for which they need to appear in the people's court. This day is not the most successful for them. They leave their little daughter Dunya to the brother of Nadya Stepanova — Nikita. But for him this is also not a very successful day: recording on the radio, an exam at a theater institute, and even a quarrel with his girlfriend...

Two KGB agents are fighting against foreign spies before and during WWII.

In 1921, the Cheka became aware that gold and jewelry were stolen from the treasury of Gokhran, and that a special organization was involved in transporting the stolen to Estonia. Scout Maksim Isayev is sent to this country. He establishes that the cipher of the Soviet embassy Olenetskaya works for the German resident Nolmar, with whom employees of Gokhran Kozlovskaya and an appraiser Yakov Shelekhes are associated. As a result of the provocation, Isayev was arrested. In the prison cell, he finds himself together with the famous Russian writer Nikandrov, who could not find himself in post-revolutionary Russia and went abroad. Released soon by the efforts of his comrades, Isayev continues the struggle for the fate of Nikandrov — for his return to his homeland.

The Nazis planted explosives to blow up the cities of Krakow and Prague, but the underground resistance in Poland works with the Russians to stop the disaster.