The action of the epic film takes place in the second half of World War II. The plot focuses on the liberation of European countries from German occupation and the anti-fascist activities of the communist parties of these countries. After the victory at Stalingrad, a decisive turn occurred during the war. The main aim is the rallying of all patriotic forces, the creation of a national anti-fascist front in the struggling countries. The swift offensive of the Soviet troops, problems with the opening of a second front, major operations and the offensive of the Soviet army lead to the liberation of Europe. Rebellions are rising in different countries - such as the heroic uprising in Warsaw, in Slovenia, Bucharest and other cities. Brave heroes who performed immortal feats in the name of the happiness of mankind and freedom.

1942, Polar region. The Germans are preparing to capture Murmansk. The submarine Sch-721 is considered lucky, and its captain Aleksei Strogov has the ability to extricate himself from the most difficult situations. He also develops tactics for a periscope-free torpedo attack, despite the skepticism of colleagues and management. And now, when the Happy "Pike" had to take on board the crew of another Soviet submarine, and she was on the seabed with almost no oxygen, Aleksei manages to save people and perform the operation, paying for it with his life...