Two siblings cruise on their Hover bikes until a colossal Metal Fortress obstructs their path. Following a fierce altercation, the brothers deal a fatal blow to the fortress, causing it to withdraw and strand them in a desolate landscape. To their surprise, nomadic dwellers reveal that the fortress lurks within a nearby mountain. Urging the brothers to complete their mission, the nomads enlist two of their own as guides. Along their journey, they encounter a mystical faery capable of morphing into a formidable mech-warrior woman, adding a powerful ally to their quest.