The "Haiyan Tower Murder Case" 20 years ago has become an unsolved case, and now a secret room murder reappears in the old location. The protagonist Lin Shen's investigation found that the two cases were highly similar, involving the survivor Su Nian, the mysterious investor Shen Zhao, retired forensic doctor Lao Zhou and others. As the investigation deepened, it was discovered that the secret room was not supernatural, but an ancient institution; Su Nian's amnesia was due to human intervention; the case was intervened by the powers that be; and it was finally revealed that the real culprit was actually directed and acted by the old man of the Su family, who killed his family and framed others for the treasure. Lin Shen finally fulfills his father's last wish and reveals the truth, but the anonymous letter indicates that there are more secrets.
