A Russian investigator and a Buryat policeman are investigating the murder of a truth-seeking huntsman in the Baikal taiga.
An expedition group led by Professor Shestakov arrives in one of the regions of Siberia to search for diamonds. The research begins with a dramatic event: The expedition leader dies suddenly. However, the geologists decide to continue the difficult, dangerous hike along the taiga "diamond trail".
Based on Anatoly Tobolyak's story "The Story of One Love" (1975). Newlyweds Sergey and Katya, who graduated from school only a few months ago, come to Siberia to work. Life is not quite well, but love helps to overcome adversity.
