Chinmoku no Kantai

Captain Shiro Kaieda takes the nuclear submarine Seabat beyond American and Japanese control. Pursued by the United States Navy, he announces that his vessel is now the independent nation of Yamato, turning a military defection into an international crisis.

Kaieda heads for Japan to seek an alliance as naval forces close in and political leaders struggle to respond. A single submarine becomes the center of a confrontation over sovereignty, deterrence, and who has the right to command its power.