In a world where humanity faces the threat of the abyssal fleet which has taken over the seas, special human girls who don weaponized outfits and possess the spirit of historical naval vessels known as kanmusu are the only ones capable of countering them. The kanmusu live together at a naval base, where they spend their everyday lives as they begin training for battle.
The series features the destroyer Fubuki as the main character, with the storyline based on her point of view. Fubuki arrives at the naval base, where she meets other girls that she will eventually fight alongside. Despite lacking adequate combat training, she is recommended into the Third Torpedo Squadron by the admiral, and quickly finds herself sortied into battle. Upon being rescued by Akagi in a dangerous situation, Fubuki strives to do her best in order to train, with the hopes of eventually being able to fight alongside Akagi.