Boom Boom Kitty: ブームブームキティ (Būmubūmukiti)

A gigantic craft of unknown origin crash-lands on Earth. Two of its occupants are able to escape the wreckage and hide among us. The ship seals itself off as it becomes surrounded by a hostile military. Trying to avert disaster, the two survivors form an all-girl band which they call Boom Boom Kitty, and use the band to try to surreptitiously communicate with the ship's occupants.