Young Polya comes to Moscow: she wants to find her father, Professor Vikhrov, and try to understand why her mother broke up with him. Vikhrov is a prominent scientist who has defended the forest from barbaric destruction all his life. The war begins. Professor Vikhrov continues to lecture, proving to students the need to protect the forest. Polya is trying to find out the reasons for the long-standing feud between her father and academician Gratsianskiy. Now, when Vikhrov is already not young and lonely, the professor mentally returns to the past.

Everything is behind him: fleeing from Nazi-occupied Estonia to Germany, searching for work in foreign cities, and his own crimes.... Everything is realized and decided - it is necessary to return. But when he returned, he found neither home nor relatives. His father's friend, the leader of a gang of nationalists, told him about his difficult past. Joining his gang, the hero decides to take revenge ...

Two stories ("The feat of the soldier Mukhin", "The Last Autumn"). The events of one concern 1917, when Lenin had to hide in Finland, the second takes place in 1923-1924 during the last months of his life in Gorki.