High school seniors Mikayo, Chuko and Kei are forced to join a historical research club to fulfill a graduation requirement. Their teacher, Mr. Kachi, plans a mandatory club trip to a small village called Oshakabe in Yamagata prefecture to study remnants of an ancient clan of warriors called the ochimusha who displayed legendary cowardice in battle. When they arrive, the local villagers hold a special ceremony and construct a "super shrine". As a result, an 800-year seal is broken, unleashing a curse that causes the ochimusha to rise from the grave.
