The game takes place in the mystic oriental land of Gensokyo, as usual. The story revolves around the appearance of a thick red mist, that has covered the land and blocked out the sun. Playing as either Reimu Hakurei (a shrine maiden) or Marisa Kirisame (a playful magician), you must battle your way through 6 difficult stages toward the source of the red mist, and face the "Scarlet Devil" behind i...