During the naval battle of Midway in WWII, the battleship Mutsu was in its home port in Japan. The ship's officers and crew were frustrated at not being able to take part in the fighting. They had been held back by orders from the Naval Ministry, but there was also a plot by saboteurs, who were trying to prevent the sailing of the Mutsu. Director Komori developed a suspenseful plot by including a fictional adaptation of the Russian spy Richard Sorge, who had been captured in Japan and subsequently executed. Komori brings a fictional Russian spy to the screen by portraying him as a military attaché at the German embassy. As Germany was an ally of Japan in WWII, a secret agent being a mole in the German embassy is a perfect cover. The interaction of the saboteurs and the officers and crew of the Mutsu make an exciting story.