In the near future the world's climate shifted creating in the Western Pacific a perpetual super cyclone: the Grand Roar that alterted the earth, flooding most countries. Shipping and navigation became important to nations and followed by the specter of ocean pirates thus necessisating companies to hire escort cruisers to safeguard their investments. Hyousuke Nagimiya is a system engineer that was comissioned to upgrade the Pascal Magi manned by an entire crew of women with its captain, Misaki Nanaha. Together the crew strives to prove themselves to their detractors that they are no mere 'Alice Brand'. Yet as they go about their mission a larger global conspiracy seems to be working behind the scenes to take advantage of this new world order.