Brigadoon

Marin, a junior high school girl from a loving adoptive family, lives a typical life in 1969 Japan. However, her world is disrupted by the appearance of a mysterious mirage in the sky, followed by the arrival of killer androids called Monomakia from a formation known as Brigadoon. Marin's search for escape leads her to a shrine where she discovers a blue bottle containing Melan Blue, an alien with a sword and gun, who becomes her protector.