Yokosuka Girls' Marine High School buzzes with activity as they host competitive games against other all-girls maritime high schools. Amidst the excitement of festivals and tournaments, students from various years come together, forming bonds and facing challenges. Akeno Misaki, the captain of the esteemed Harekaze class, grapples with conflicting emotions when her instructor offers Mashiro Munetani, the executive officer, a chance to lead the Hiei class. This decision places a weighty dilemma on Mashiro and prompts Akeno to address the unfolding circumstances. However, their troubles escalate when Yokosuka encounters a crisis—pirates have seized control of a vital water purification plant and sea fortress, jeopardizing maritime safety. Now, Akeno and Mashiro must navigate the chaos as they lead the Harekaze class through this perilous situation, all while contending with their personal challenges.