In a small Swedish town, the murder of Frome, the owner of a public relations research firm, takes place. A day later, his friend Touraine, the police commissioner leading the investigation, is killed...

In September 1944, an unusual train travels to the Turkish border. Abroad the train are German fascists and Bulgarian King's officers who carry important papers and archives. A group of partisan chases the fugitives with a track. Soon airplanes with red stars on their wings could be seen in the sky. The planes are reinforcements from the Soviet aviation squadron. With its help the partisans capture the fugitives.