Civil war. Polish interventionists approach Berezina. The Red Army temporarily leaves Belarusian lands. Partisan detachments are organized, one of which is led by Bolshevik Stepan. His brother, who is in collusion with Polish spy Kapusta, is also in this detachment. With Kapusta's help, Polish lancers who have appeared in the village reach the partisan camp and capture the headquarters. Yanko manages to warn the headquarters about the movement of the White Poles, and the partisans are forced to retreat through impassable swamps. They manage to escape and join the Red Army, which occupies Minsk on July 11.

A film based on the life of the Russian scientist, Klement Timiriazev, who taught at Cambridge and Oxford and was awarded the Newton Mantle for his work. Timiriazev, one of the few outstanding Russian scientists who (publically) backed the Soviets in their revolutionary campaign, was later elected a delegate to the Leningrad Soviet by the sailors of the Baltic fleet. There he denounced his fellow scientists for failing to aid the Soviets and predicted that such aid would come.

Soviet sailors boldly defend Leningrad from the German fascists.

The 1930s. Naval maneuvers are underway. On orders from the command, three submarines are to "attack" a battleship. In the heat of the "battle," a fourth periscope appears. Where did the fourth submarine come from? Is it one of ours or an enemy vessel? These questions must be answered immediately by the commander of the destroyer "Otvažny," otherwise...