One day in the distant future. Humans live shoulder to shoulder in "colonies" separated by rock. Outside the colonies, a dangerous undeveloped area called "the Labyrinth" is expanding. Those who risk their lives to develop "the Labyrinth", who mark out the undeveloped areas, are known as "Markers". A young girl, Memempu, who wants to be a Marker one day, and a man, Gagumber, who used to be one. This mismatched father and daughter now take on the Labyrinth! "If there's no path, dig one!"