Business is sluggish at the Ootsuji Detective Agency. Soutarou and his youthful assistant Saki will accept any assignment that surfaces, even those that appear far riskier than they seem. The city is in festival mode yet hidden from public view, a surge of perplexing vanishings has taken place. A journalist contracts Soutarou to probe the case, hinting that solutions may lie within the Dark, the infamous, chaotic labyrinth that forms the city"s physical, social, and ethical underbelly. Soutarou delegates the task to Saki, but quickly regrets it when the boy also disappears. Consequently Soutarou must delve into the Dark himself, facing its shady underground inhabitants, such as the vicious Laughing Masks faction and the rogue police unit steering the dreaded Demon 463 armored locomotive and the city"s trembling shadows await.
