In a world that looks like the 19th century with anti-gravity devices, Claus and Lavie are pilot and co-pilot of a Vanship and act as couriers. They become involved with a mysterious mission after rescuing a little girl from a strange star-shaped killing machine.

Not willing to let the girl die, they complete the mission by delivering her to the legendary mercenary ship Sylvana, only to become part of the crew as fighter pilots.