In a post-war alternative timeline, Japan is divided into the North, controlled by the Union, and the South, controlled by the United States. A mysterious high tower rises within the borders of the Union. Three high school students promise to cross the border with a self-built airplane and unravel the secret of the tower.

Cast: Hidetaka Yoshioka, Masato Hagiwara, Yuuka Nanri, Unsho Ishizuka, Kazuhiko Inoue, Risa Mizuno