High school student Aoi Nishino is a history enthusiast who participates in his school's archery class. Because of his archery skills, he occasionally feels he would have been better suited to Japan's Sengoku period. He imagines that if he had lived back then, he might even have had a wife like his clubmate Seno. In reality, Seno is his friend and the girlfriend of his childhood friend Kouta. When a mysterious fog envelops the school, Aoi gets the opportunity to experience the Sengoku period firsthand. The entire school is transported to a time period that Aoi identifies as somewhere between 1576 and 1582, near Azuchi Castle. However, things are not as rosy as he might have imagined. Armed men accompanying the historical figure Koroku Hachisuka attack the school, brutally murdering teachers and students. Will Aoi and his friends be able to survive this deadly era?