Ruka is a young girl whose parents are separated and whose father works in an aquarium. When two boys, Umi and Sora, who were raised in the sea by dugongs, are brought to the aquarium, Ruka feels drawn to them and begins to realize that she has the same sort of supernatural connection to the ocean that they do. Umi and Sora's special power seems to be connected to strange events that have been occurring more and more frequently, such as the appearance of sea creatures far from their home territory and the disappearance of aquarium animals around the world.
After he's attacked on the street at night by a roving motorcycle gang, timid bookkeeper Casey joins a neighborhood karate studio to learn how to protect himself. Under the watchful eye of a charismatic instructor, Sensei, and hardcore brown belt Anna, Casey gains a newfound sense of confidence for the first time in his life. But when he attends Sensei's mysterious night classes, he discovers a sinister world of fraternity, brutality and hyper-masculinity, presenting a journey that places him squarely in the sights of his enigmatic new mentor.
The reality behind a hideous crime is yet to be unveiled as a reporter's wife dives deep within the depths of despair and darkness to seek the truth of her missing husband.