Nine volunteers begin digging a tunnel through rugged mountain terrain. The group includes three miners. The others have come from different parts of the country for different reasons. When winter comes, a blizzard makes the road impassable and the truck with supplies cannot reach them in time. With only a hundred metres to dig, the tunnel collapsed. Everybody leaves the construction site, except the communist Damjan. In town they check in at the mine and are due to start work in two days. During these two days, one by one, they are overwhelmed with shame for leaving the tunnel, and finally return to Damjan to finish their work despite all the difficulties.