The film is a reflection on the responsibility of man to other people, native nature and the world around us, the problem of preserving Lake Baikal, on the banks of which a large construction project has unfolded. The first half of the 60s of the XX century, the story of the love of young Lena Barmina to an adult respectable person, bearing on his shoulders a heavy burden of responsibility for the activities of a huge enterprise. Construction engineer Chernykh and Lena, the daughter of a scientist, are doing everything to save the lake from harmful and unjustified plums. A difficult relationship develops between them and soon Lena realizes that she is in love. But after learning that Chernykh is married, the girl leaves...
Having returned from the army, 20-year-old Sergei settles down at the thermal power station and merges into ordinary life. Every day he meets and spends time with childhood friends — the young family man Slava and the merry fellow Nikolai, and once at first sight he falls in love with a stranger on the bus. A lyrical story about a generation of young people entering adulthood, a reappraisal of values, life principles, traditions in culture and art.
