Chronicle of the After-School Wars (Hôkago senki) theatrical trailer - Junpei Tsuchida-directed J-horror

[Not to be confused with the filmed stage play - likewise titled "Hôkago senki", and likewise starring Miori Ichikawa - which was released on DVD in Japan on July 4, 2017 (HPBR-140).] Synopsis for Junpei Tsuchida's Chronicle of the After-School Wars (Hôkago senki) from Nikkatsu International Sales (Nikkatsu Corporation/Nikkatsu K.K.): "One day after school, Sena Kadowaki has dozed off at the school rooftop, while she is waiting for her classmate Yudachi Tsutsui to return her handkerchief. When Sena is awakened, she is closed in the dark school building. Then, it is a suffering girl whose hand is cut down that is found inside the building where mobile phones refuse to work, which is totally isolated from the outer world. In the world, the sky is crimson like the color of blood and a huge light unlike sun is seen. As these strange happenings come to pass, school girls start shivering, killing fights with one another. Who is the mastermind of the horrible battles? And can Sena defend herself from the girls' ferocious attack?"