The mining town of Donetsk with specifically difficult mining and geological conditions. To the new chief engineer Marat Zhukov, the mine directorate sets the task to close the dangerous lava, where the Dotsenko team works - one of the best mines has ceased to fulfill the plan. Having made the calculations, Marat discovered the possibility of reaching the normal layer and he was able to convince the authorities that it was not necessary to disband a friendly team.