Episode 13 of Miss Night and Day delves deeper into the complex web of
mystery surrounding the serial killer case, while also developing the budding
romance between Lee Mi-Jin and Gye Ji-Ung. The episode maintains a balance of
suspense and heartwarming moments, keeping viewers engaged throughout.

The episode commences with the aftermath of Ji-Ung's declaration of feelings for Mi-Jin. Their blossoming relationship is evident through their playful text exchanges, yet Mi-Jin remains cautious about their public display of affection. Meanwhile, investigator Byeong-Deok notices the unusual closeness between Lim Sun (Mi-Jin's older self) and Ji-Ung, adding an element of intrigue to the narrative.
The focus then shifts to the ongoing investigation. Baek Cheol-Gyu, the hospital director previously suspected of being involved in the serial killings, provides a crucial piece of evidence to Lim Sun during their interrogation. This unexpected turn of events leaves both Ji-Ung and Byeong-Deok puzzled. As the investigation progresses, Ji-Ung becomes increasingly curious about Lim Sun's connection to Cheol-Gyu, unaware of their shared past.
Amidst the unfolding mystery, the romantic subplot between Mi-Jin and Ji-Ung continues to develop. Their interactions are filled with sweet moments, but the challenges posed by Mi-Jin's dual identity create a sense of uncertainty in their relationship. Ji-Ung's growing suspicion about Lim Sun's behavior adds another layer of complexity to their dynamic.
The episode concludes with a cliffhanger as Lim Sun receives threatening messages demanding her identity be revealed. The source of the threats is eventually traced to a secluded house, where Lim Sun discovers a shocking connection to her past. The revelation that the threats are targeting her former colleague, Na Ok-Hui, introduces a new mystery into the plot. The episode ends with a tantalizing question: Is Na Ok-Hui the missing suspect, Gong Eun-Sim?
Overall, episode 13 of Miss Night and Day successfully blends romance, suspense, and character development. The episode effectively builds anticipation for the upcoming episodes as the plot thickens and the characters navigate their complex relationships and the ongoing investigation.