The bridegroom Jan Kaspar is an officer in the Klement Gottwald's Nová Hut rolling-mill. After bidding farewell to his freedom, he accidentally takes a sip from the bottle of tetrachlore which he stores at home. He disregards the dizziness, but the next day, he faints in the factory and has a brain concussion. During her regular tests, doctor Dudková is shocked by a high percentage of residual nitrogen found in Kaspar's blood. Doctor Bohácek, with whom Dudková consults, thinks that it is a liver disease and informs the head physician Filip. The doctors know nothing about tetrachlore and are in the dark about the case. Despite that, they immediately start to fight for Kaspar's life and their struggle consequently affects their personal lives.