Late one night, a UFO is spotted over Japan. After a run-in with a strange, insectoid creature that leaves a few humans in suspended animation, a Defense Council meeting is held as to what to do with this potential menace from another world. Captain Muramatsu decides the best way is to attempt to communicate with it. When this goes sour, the aliens, called the Baltans, take control of Arashi's body and declare their true purpose -- to colonize the Earth with their own race, billions of which are already here, in microscopic form and aboard a cloaked ship.