The story takes place over a 24 hour period. In the southernmost part of Japan, 20 fishing boats of an unknown nationality suddenly fire upon and occupy parts of the Hateruma archipelago. Members of the Japan Coast Guard are detained. Under the extremely tense situation, the Japanese government sends Aircraft Carrier Ibuki and an escort fleet to the area. Ryota Akitsu is the captain of the Aircraft Carrier Ibuki and Toshiya Niinami is second-in-command. It is now 6:23 am. and Japan faces one day which they never have before.
Hidetoshi Nishijima
Tsubasa Honda
Koichi Sato
Kuranosuke Sasaki
Jun Murakami
Tatsuya Fuji
Shigeyuki Totsugi
Hayato Ichihara
Hiroshi Tamaki
Jin Katagiri
Hisahiro Ogura
Kiichi Nakai
Tatsuya Fujiwara
Mai Fukagawa
Hoshi Ishida
Toru Masuoka
Ikuji Nakamura
Kinari Hirano
Shunsaku Kudo
Chiba Tetsuya
Yoshikuni Dôchin