Lin Yan, a modern senior female forensic doctor, accidentally traveled to the Jingyao Dynasty with backward legal system due to a laboratory accident, and was accidentally involved in a murder case. With her precise autopsy skills, she helped Gu Yunzhou, the young minister of Dali Temple, to identify key clues and temporarily avoid the suspicion of "demon".
In order to gain a foothold in another world, she joined the Dali Temple as a "trainee" and used modern forensic knowledge to repeatedly solve strange cases - identifying drowning as murder, identifying the real culprit from the remains of burned corpses, and relying on homemade reagents to distinguish poisons and clear the wrong.
As she and Gu Yunzhou grew from doubt to trust, her identity was criticized by the court while investigating the murder of a powerful figure. In the end, Lin Yan used irrefutable evidence to uncover the prime minister behind the scenes, and was granted an exception by the emperor. He stayed in Dali Temple as a widower, not only promoting the advancement of dynasty autopsies, but also joining hands with Gu Yunzhou to write a legend of justice that spans time and space.