The Netherworld Brush Hunts Killers: A Conversation Between Police Souls Across Thirty Years

One side is the 1980s, where criminal investigations lag behind and strange incidents are frequent. The other is a future city with advanced technology but haunted by old cases. One spectral pen bridges thirty years of life and death.

As the two join forces to solve long-unsolved cases, one terrifying supernatural incident after another unfolds: a woman in red appears on a rainy night, case files turn their pages by themselves, corpses refuse to decay, vengeful spirits send messages through the pen, and a curse in the form of a blue mark coils around a wrist... They gradually discover that every unsolved case points to the same serial killer, whose crimes span thirty years. The secret of the pen, the truth behind an old detective's suicide, and the eerie pursuit across time are all far more frightening than ghosts.

The more cases they solve, the deeper the curse grows. They must not only hunt down the killer and lay the spirits to rest, but also fight back against the backlash of time itself. As the truth is revealed layer by layer, they finally realize that this conversation across time was fated to be a carefully laid plan from the very beginning.