The beginning of the 30s of the last century. A leak of classified information was found at the Soviet shipbuilding plant. Arriving under the guise of a scientist, the legendary chekist Karotin begins to unravel the threads of the conspiracy of the fascist spy organization. He is helped by inexperienced but active local detectives. Mastering the basics of the counterintelligence, they fall into a situation the other one funnier.

The action takes place in the late 1940s. A large-scale land-surveying research is underway in a remote area of Eastern Siberia. The work had almost been concluded when a wire arrives with the news of people disappearing in the locality of Yambuy. The expedition’s chief and radioman decide to go in search of the lost ones. The local Evenk hunters come to their aid. Many dangerous adventures lie in store for these daring people before they find the culprit – a man-eating bear.