The Soviet motor ship "Albanov", running into a submarine rock, crashes in North sea. Passengers and command on boats head for off-shore rocks and find temporal shelter. Getting a signal about the calamity of motor ship, detachment of divers-rescuers at the head with the chief of party - commissar Petrov - begin works on getting up "Albanov".

In 1921. With the help of Japanese interventionists, the White Guards defeat a Shaldyba partisan detachment. The remnants of the defeated detachment pour into Levinson's detachment. Partisan intelligence soon finds that the Japanese has surrounded the detachment. To save the main forces from defeat, Levinson decides to break through the chains of enemies.