The new supervisor Vasil arrives at the construction site of a dam. Vasil has problems with his men, who mistrust him and reluctantly submit to his perfectionism. He becomes involved with the refreshment bar attendant Lilyana. Vasil, who always wanted children, cannot abandon his childless wife and breaks with Lilyana. When four workers are buried in a tunnel landslide, Vasil makes his way to them and manages to drag them all out, except for Zlatan, a spiteful egocentric, whose legs are caught under a fallen prop. Zlatan begs Vasil to save him, even if it means cutting of his legs. To release the miner's legs Vasil cuts the prop, which is also supporting the roof of the tunnel. Zlatan is rescued. However, Vasil is killed. Since then, the workers say his steps can be heard bellow the dam wall.

A tenement house needs to have steam heating installed. The residents find the necessary workers to do it, sign the contract and pay them in advance. The workers show up and start their job, but disappear immediately. Panic-stricken, the residents set up to search for them, only to find the workers in jail. Totally desperate, their only chance is to come up with an ingenious plan how to bring the work to the end.