Submarine 707R

Eleven nations unite their navies to form the Peace-Keeping Navy (PKN),a joint force created to counter the terrorist group "USR." But during the PKN's first official ceremony, Admiral Red and his USR submarine, the UX, launch a devastating attack, wiping out most of the fleet. Just as the UX prepares to deliver the final strike to the flagship Apollo-Norm, the outdated Japanese submarine 707 suddenly appears and takes the hit, saving the carrier at the cost of its own destruction. Half a year later, Captain Youhei Hayami is recalled to service. Tasked with leading a fresh crew, he takes command of a newly built 707 submarine, diving back into the underwater battle against terrorism.