Students, including Aoi Nishino, take part in class and sports activity at a prestigious high school. Aoi Nishino is a member of the school's archery club. He practices archery studiously and doesn't socialize much with the other students. His childhood friend Haruka Seno is also a member of the archery club, but she worries about Aoi Nishino. One day, thunder strikes the school grounds. After that, the ordinary lives of the students changes drastically. Many samurai descend on the school grounds. It appears that the entire school has traveled back in time to the Sengoku period. Making things worse, they realize that they are in the time right before the Battle of Okehazama takes place.
Like most students Aoi is a member of an extracurricular club at school and practices archery. Due to ample practice, Aoi is good at it. The members are mostly good friends. All is well until blitz and thunder hit the premises and the school and its students are not the same anymore. They are transported to a different era, one in which samurai roamed Japan. The students are not only caught in an anachronism, but they are also in the midst of a historic battle.