Lin Zhao, an associate professor of criminal psychology, was commissioned by the police to participate in the profiling of serial murders. He discovered that mysterious blood marks appeared at the death scenes of all the victims, and they were highly overlapped with the traces at the scene of his mother's mysterious death twenty years ago.
When she was trying to crack the symbol code, she unexpectedly met Shen Yan, a cultural relic restorer who could not only decipher the ancient book information hidden in the symbols, but also had a secret connection with her mother's old case.
As the investigation deepens, the two gradually uncover the supernatural truth about "obsession embodied murder": the murderer is actually a "puppet" controlled by the resentment of the deceased in the old case.
When twenty years of grievances intertwine with seven murderous cases, Lin Zhao must make a choice between legal justice and human redemption, and finally use self-discipline and rationality to disintegrate this "obsessive revenge" that spans time and space.
