Upon the arrival of the technologically superior alien force known as the "Sirens," humanity was compelled to unite for the very first time. Together, the Eagle Union, Royal Navy, Sakura Empire, and Iron Blood formed Azur Lane, which proved victorious in their initial battle against the common enemy. Unfortunately, opposing ideologies created a divide, causing the Sakura Empire and Iron Blood to create the Red Axis, thus fragmenting humanity once again. As the skilled fighter known as the "Grey Ghost," Enterprise must lead Azur Lane to triumph, even as she conceals a fear of the ocean behind a stoic facade. Regardless, Enterprise persists, knowing that it is her sole purpose. In the meantime, Javelin, Laffey, and Unicorn form bonds of friendship with Ayanami, a spy from the Red Axis, despite being fierce adversaries. Despite constant conflict, the solution to unite humanity might lie in accepting our mysterious nature as individuals, as well as through camaraderie between those with differing ideologies.