Todor Primov is an officer of the royal army who changes sides and goes over to the partisans. After the war, he graduates in engineering and is appointed manager of several construction projects. His car crashes on the eve of March 13. After his recovery, Primov resumes his work. Yet, secret information starts leaking from the projects and some serious accidents occur. Andrey, who befriended Todor Primov back in the partisan unit, goes to investigate the causes. He knows that Todor was colored-blind while this engineer distinguished colors. Andrey manages to get at the truth: Parvan Primov, Todor's twin brother, has made the car crash. On that night he killed his brother and took his place...

The film tells the story of a young village girl who leaves home for a factory during World War II, lured by promises of easy money and a good life. Soon after arriving at the factory, however, she realizes that all the promises were lies, but Danka will not give in to discouragement. After the liberation of Bulgaria by the Soviet Army, she happily went to work with the other workers in the factory, which now belonged to the people.

The Soviet army is approaching the Bulgarian border. Many government ministers and army officers prepare to flee the country. The partisans take over the key administrative buildings. At the War Ministry, the commander of the armored brigade Major Essev hesitates between his sense of honor as an officer and his patriotic duty. He takes the side of the partisans.