Stamen, a civil engineer, gets a new appointment. He has to leave the capital and his friends for the building site of a huge dam. On the train, he meets Katya. He thinks she is an actress and shares with her chagrin at his new job. His instant disappointment with the dismal working and living conditions on the construction site only adds insult to injury. Much to his pleasant surprise, he finds out that the "actress" he met on the train, is also an engineer and even works on the same site, but this does not relieve his bitterness. One night he tries to quit without telling anybody. Katya unexpectedly overtakes him. The young engineer goes back. He goes to work in high spirits. The joint endeavor and their conversations give rise to a warm feeling between them which blossoms into love.