The life and work of Chinese bacteriologists. The film is based on the theme of profound psychological changes in a person's character, who, under the influence of many factors of life and situations, has to change his view of the world and science. One of the characters, Professor Huang, is shown in the process of development and formation. His character is vivid and memorable. If at the beginning of the film the young scientists seemed insufficiently serious to Huang, and he regarded all their aspirations to enter science as a sign of their lack of understanding of the complexity of science and their responsibility, by the end of the film Huang already sees in the young graduate students courage, daring, and a desire to achieve an active intrusion of science into life. The theme of friendship and mutual respect among scientists united by a common goal—serving the people—plays an important emotional role in the film.