Working peasants Sardioni and Yagora are friends. Yagora and fellow villagers do not know that Sardion is a foreign intelligence agent. Yagora's son, Nodar, who fled abroad during the civil war, will perform the task of foreign intelligence and sneak saboteurs into his homeland under the guidance of Sardion. Persecuted by the border guards, Nodar takes refuge in his father's house. Yagora will condemn her son's behavior and support his arrest.

A group of young geologists will try to explore the Tsani Gorge in the Caucasus Mountains. But the geologists lack the experience of mountaineers and their attempt fails. The geologists organize a hike again under the leadership of experienced mountaineers, young engineers - Osiko and Tite. The geologists are on the top of the mountain to determine the thickness of the ore layer. Suddenly, a storm breaks out. To save the geologists in danger, a rescue squad sets off from the mountaineering station. The geologists carry out their task and return safely.