The protagonist, Lin Yu, was an ordinary person obsessed with history who accidentally transmigrated to a parallel world. Its technology was on par with modern Earth, but ghosts roamed everywhere, appearing in cities and villages at night and causing all kinds of paranormal incidents that terrified humanity. Although various countries had organizations of ghost hunters to fight back, the lack of a complete underworld system to manage spirits meant the ghost menace could never be fully eradicated. The world was trapped in a state of chaos and fear. Fortunately, Lin Yu bound himself to the Underworld System, and his legendary journey began.
