It was 1999 when a huge extraterrestrial battleship crashed on Earth and brought superior technology which led to the beginning of war between the U.N and Anti-U.N. Eight years have passed and many veteran pilots were lost one after another, so now, even boys in their teens were gathered unto the battlefield to fight the war.

Shin Kudou, a young U.N F-14 pilot and the main character of the story gets shot down by a new enemy fighter during a sortie and crash landed on a solitary island.

Coincidentally, at the same time, an unusual energy reaction was detected on the island, an energy reaction which might have been originating from Protoculture's superior technological legacy which was brought by extraterrestrials during ancient times. This technological legacy is very similar to that recovered from the fallen extraterrestrial battleship eight years ago.

Now, both the U.N and Anti-U.N are going to invade the island for the purpose of recovering the legacy and the superior technology it possesses...