The story begins when a ship school, with a whole crew of cadets (supervised by some soldiers), returning from training. However, this is the time that their country is attacked and went away.
The opening theme is "Radiance" by Mami Kawada and the ending theme is "Chi ni Kaeru ~on the Earth~ " by Kotoko. While supervisors leave the ship, the young recruits decide to take control of the ship and continue fighting.