Junior Lieutenant Maleshkin, an unshooted graduate of the school, commands the crew of the self-propelled gun SU-100. All the subordinates of Maleshkin are older than him and much more experienced. The authority of the young commander is tested at every step, he quarrels, then reconciles with his crew.

The adopted daughter of Dr. Skvortsov, Tanya, having learned that her mother Natalya Avdeyevna is alive, who was considered dead during the bombing of World War II, decides to go to her in a distant village on vacation. She recognizes the woman who gave her life and lost her husband and sons due to the war, but cannot call her mother. Meetings on the collective farm with interesting people make Tanya think a lot and experience a lot. She discovers for herself a completely new, largely alien world to her. It does not immediately penetrate the sense of inner kinship with this world, its people, so unusual for her.