All three volumes of the anime series. For more than 30 years, a secret war has exploded at an inter-dimensional portal in Antarctica. Alien troops created the portal in an attempt to invade Earth, but Earth unified and developed a secret elite military force to stop the invasion. The highly advanced fighter Yukikaze contains a sentient computer system that, along with Rei Fukai (who is a member of the Special Air Force and pilot of the Yukikaze), provides the best hope of winning the war.