Bulgaria is on the eve of World War I. King Ferdinand survives an attempt on his life thanks of high-school teacher Irina Radionova. The monarch is generous in his gratitude. He assures the teacher that he will not permit Bulgaria's involvement in a war. Back in the village where she lives, Radionova learns that war has just been declared. Her son Boyan has to leave for the front. Irina becomes a nurse. At the front, Boyan is facing trial for having taken the side of mutinous soldiers. Irina goes to the King to beg for clemency. Ferdinand promises to do something about it. However, when Irina arrives back, the presiding judge tells her that the sentence has already been carried out and hands her the telegram from the King. It says that His Majesty has graciously condescended to command that Irina Radionova be granted permission to receive the body of her son
The university student Bobchev joins a youth brigade. The commander's council entrust Bobchev with a literacy course for members of the brigade. Velizarov and Monkata arrive in the camp to carry out sabotage. They place explosives on the dam, and attempt to win Bobchev over by means of intrigue. There is a storm: the camp is put on the alert. Everyone joins the rescue work at the dam. After a long struggle with Velizarov, Bobchev cuts the burning fuse of the explosive. The dam does not yield to the pressure of the flood. Everymen sing in Jubilation.
