Qiao Qingqing (played by Chen Xinyu), a sophomore student of forensic medicine, is actually a script traveler. Her mission is to enter the script, save the trapped players, and bring them back to the real world. With the help of the system Xiaoyi, Qiao Qingqing enters an unknown script and starts in prison. Qiao Qingqing learns that she is the only daughter of Qiao Bushi, the right prime minister of the Daning Dynasty. The emperor wants to take Qiao Qingqing as his concubine and sends the eunuch general Fu Qiuhai to the Qiao Mansion to issue an edict. Unexpectedly, Fu Qiuhai died unexpectedly in the lotus pond of the Qiao Mansion that night. The emperor was furious and imprisoned the entire Qiao family. Qiao Qingqing figured out a way to save herself from prison and met the black-bellied emperor Yan Junhuai. Yan Junhuai accidentally discovered Qiao Qingqing's talent for solving cases and decided to let Qiao Qingqing solve the case of the murder of the eunuch. Yan Junhuai ordered Qiao Qingqing to disguise herself and bring her back to the palace. Qiao Qingqing read the case file and found out that Fu Qiuhai's death was very strange. He was floating above the pool with green light on his body. It was rumored that this case was caused by a demon. Qiao Qingqing naturally didn't believe it, but she couldn't understand how Fu Qiuhai got to the center of the lake. At night, Qiao Qingqing wanted to go to the crime scene with Yan Junhuai to investigate, but Yan Junhuai was gentle and tender at this time, as if he had changed into a different person. Qiao Qingqing got many clues through the crime scene.