The story takes place in 2501, when a laser weapon at a defense outpost on Pluto has malfunctioned and begun destroying the Solar System. The player takes on the role of the M-308 Gunner, which storms into the defense base in order to activate the self-destruct system before the laser gun destroys Earth. The M-308 is equipped with a gravity control device which allows the player to flip between the floor and ceiling, a main feature of the game. "Metal Storm" received positive reviews from gaming publications.