Based on the novel of the same title by Daniil Granin
The story told in the film begins in 1952 and covers 10 years. Lives of two friends — Sergei Krylov and Oleg Tulin went in two different ways. Shortly after graduating from university Tulin is assigned to work on a serious project, while Krylov is expelled from university for his refusal to consider cybernetics to be “a false science”.
Showing great persistency Krylov grabs the opportunity to work in a research institute under the guidance of the noted scientist Dankevich, but in a difficult moment cowardly leaves the project and goes on a research expedition to collect materials for his theses.
Having achieved success and having got the position of the chief of a laboratory Krylov begins a new research project and invites Tulin to work together, but fate finally pays him back for leaving the project.