After a fierce battle that seemed to seal her fate, the Aircraft Carrier Zuikaku awakens to a startling revelation—she is now a 'Ship-girl,' a young girl with powers and memories from a bygone war. Reuniting with her sister Shoukaku, they join forces under the guidance of the Admiral to face a new enemy: the Abyssal Ships. Determined to safeguard a world reminiscent of her past, Zuikaku returns to the battlefield, grappling with the harsh realities of her own destiny.