"Yes, Ootsuji Detective Agency" In the purple smoke lies a faint dream, and in the town, rumors swirl like smoke. Now, facing the strangeness of the "mass disappearance" bewildering society, detective Soutarou confronts it! With no witnesses and unclear intentions, the identity of the "ominous tracks" that always appear in its footsteps... In search of clues, the detective delves into the underground realm of the town called "Kuragari." There, the encounter with the black iron armored train and its commander, Tanne, will significantly shake the fate of the detective!
Will they discover a secret 
realm untouched by man?
هل سيكتشفون منطقة سرية
لم يطأها بشر؟
Ein Ort, den keine Menschenseele
je betreten hatte?
Encontraron un lugar inexplorado
por el hombre. Sin embargo,
Encontraron un lugar
inexplorado por el hombre,
Allaient-ils découvrir
une région inexplorée ?
Hanno scoperto un luogo
 dove l'uomo non ha mai messo piede?
Encontraram um lugar inexplorado
pelo homem. Contudo,
Быть может, по ту сторону
лежит неведомый человеку мир?!