The story takes place in a fictional future world. At that time, humans lost control of the sea due to negligence and carelessness. The ocean became a place that people could only dream of but could not reach. There was a powerful force called "deep-sea ships" entrenched there. In order to fight against this force, a group of girls called "ship girls" appeared. In their bodies, the souls of ships inhabited, and they were transformed into various warships, making unremitting efforts for the peace of mankind. On weekdays, the ship girls carried out their daily life and training in the base camp called "Navy House". One day, a lively girl named Fubuki (voiced by Sumire Uesaka) appeared in front of everyone. She was full of confidence and enthusiasm when she first arrived. She joined the new life of the fleet. Here, a wonderful and exciting daily life unfolded.