Song Lei, a corporate worker who died suddenly in the mortal world, becomes a probationary bailiff in the Underworld's Extradition Department. To pay off a high-value points debt, he teams up with Judge Cui Jue, A Cha, the ferryman Lao Zhou, and underworld merchant Su Mei to investigate desire-eating ghosts, unexpectedly unearthing an old case from a millennium ago where Cui Jue released deceased souls in private. Together, step by step, they uncover the conspiracy of Liu Yan tampering with the Book of Life and Death and framing deceased souls. Song Lei grows through these trials, gets elected as a rule-revision envoy, and pushes the nether administration to establish an appeal channel for deceased souls. Before the dust of the old case settles, new obsession-driven ghost cases emerge one after another, and Song Lei and his group continue to run back and forth between the mortal and nether realms, guiding lost souls and breaking deep-seated abuses.