Koji Namiki, a talented young pitcher, who had won the National High
School Baseball Championships enters university, but soon afterwards
injures his elbow. He and his teammates work hard to get back on the
field placing all his hopes on a new slow-ball, "the magic pitch."
However, the outbreak of WWII wipes out the baseball ambitions from
everyone. They join the military and in the navy undergo the severe
training that prepares them for death. Death awaits them in a "kaiten"
(special attack submarine or "human torpedo") within the gloomy ocean
depths, but Koji never gives up his dream of the "magic pitch."