Ocean crime is on the rise and it’s keeping the Anegashima police department very busy. Samejima and Orpheus get a personal call from Captain Jinguji of the mysterious Foreign Ocean Affairs Section Seven’s Mobile Investigations Unit. According to her sources, several members from the ocean gang known as the Osawara Family are on the move. And many of these bad-boy fishmen have it out for Orpheus, including one of their higher-ups, Kinnosuke Kaji. But what could this fiendish marlin be after on land? And more trouble is brewing when Jura accuses her boss—a former member of the Cult of the Sea—of trying to murder her coworker and friend Yukari!