A paranormal investigator is caught up in an unusual criminal revenge case – the guilty one is always a goldfish. One death follows another, always different and very violent. The causes lie far back in human history.

In mid-19th century Edo period, a masterless rōnin named Mokunoshin Tsuzuki resides in a peaceful village among those he helps. However, as the prevalent peace and tranquility are sure to be replaced by war and conflict across the land, the swordsman feels restlessness creeping upon him.