In Chang'an of the Tang Dynasty, undercurrents surged under the night.
The minister of Dali Temple, who is guilty of a crime, bears a stigma but is obsessed with the truth. He uses his meticulous mind and proficiency in criminal law to search for clues in desperate situations;
The emperor's secret guard, who carries the emperor's orders, acts secretly and ruthlessly, is the emperor's sharp blade in the dark night, but also has an unknown past;
The prime minister's daughter is both talented and beautiful. Although she lives in a boudoir, she still cares about the world. With her insight into the court and extraordinary wisdom, she provides key information and assistance to the team;
The female widow of a famous doctor inherits the medical and autopsy skills passed down from her family, and solves the mystery in the details of the corpse. She is the key figure to reveal the truth about death.
These four people gathered together due to a mysterious case involving the imperial power and the court, and formed a secret team called "Dark Night". They shuttled through the dark night of Chang'an, struggled in the foggy and unresolved cases, and survived in the cracks of intrigue. Some people work to clear their grievances, some people work to fulfill their mission, some people work to protect their homeland, and some people work to pursue the truth. They teamed up to solve a series of seemingly unrelated but actually interlocking strange cases, uncovering the darkness and conspiracies hidden in the prosperous age of the Tang Dynasty. Before dawn, they burned their own light and heat for the peace of Chang'an.
Dai Suiqing searches for the truth, the secret guard hides the past, the rich man is wise and the widow is in the light, guarding Chang'an at dawn in the dark night!
