Investigators Lu Lingfeng and Su Wuming return to Chang’an under the pretense of escorting a royal tribute, but soon find themselves entangled in a series of baffling crimes and political conspiracies. As they uncover hidden truths behind each case, their pursuit of justice draws them into a dangerous struggle that could decide the fate of the empire.

The Tang Dynasty's grandeur continues, but hidden dangers lurk beneath the prosperity, and a storm is brewing. Various forces are on the move, triggering frequent mysterious incidents among the common people. What kind of supernatural mysteries will Lu Lingfeng and Su Wuming encounter on their perilous journey? The road to the west is unpredictable.

In Chang'an City, a mysterious herb called Black Tea causes a stir, coinciding with a string of missing bride cases. General Lingfeng of the Jin Wu guards is tasked with uncovering the truth. Along the way, he encounters Su Wuming, a sharp detective and disciple of Di Renjie. Together, they unravel a web of supernatural mysteries and dark conspiracies threatening the city.