During the construction of the Kurobe Dam, an ancient artifact was discovered, and so the United Nations Kurobe Research Institute was established. Intellectuals from all over the world gathered to study the object, and the children of those researchers attend Mt. Tate International Senior High School, including the institute head's daughter, Shirahane Yukina. In the summer of 2016, a lone samurai once again awakens. Source: ANN Note: The first and second episodes received an early screening at a special event held on 27.03.2016. The regular TV broadcast started on April 7, 2016.