Episode 9 of Miss Night and Day picks up right after the cliffhanger of the
previous episode. Mi-Jin leans in for a kiss with Ji-Ung, but things get awkward
when he pulls away at the last second. Embarrassed, she confides in her friend
Ga-Yeong, and their laughter fills the air. Meanwhile, Ji-Ung grapples with his
own conflicting emotions.
The focus then shifts to Ji-Ung's determination to solve the case of the serial missing and killing incidents. His suspicion falls on Baek Cheol-Gyu, and a new lead emerges. However, his pursuit of the case puts him at odds with his superiors.
Back at the office, the tension between Mi-Jin (as Im Sun) and Ji-Ung is palpable. Their awkward interactions are further complicated when Im Sun is seen having lunch with the young top star, Ko Won. This playful exchange fuels jealousy in Ji-Ung, especially after his subordinate, Byeong-Deok, witnesses the scene and finds it suspicious.
Later that night, fate throws Mi-Jin and Ji-Ung together again, along with Ga-Yeong and Byeong-Deok. During dinner, a hypothetical question about Ko Won's feelings for Mi-Jin sparks Ji-Ung's jealousy, prompting him to lash out. This outburst, orchestrated by Ga-Yeong, nudges Ji-Ung closer to acknowledging his true feelings for Mi-Jin.
The next day, Byeong-Deok's suspicions about Im Sun and Ko Won deepen after witnessing their closeness once again. Meanwhile, Ji-Ung makes a gruesome discovery - a body floating in the reservoir where he previously suspected foul play. This news sends shockwaves through the team, and Cheol-Gyu's suspicious behavior further fuels the fire.
As Im Sun, Mi-Jin becomes aware of the body and recognizes it as one of the missing senior citizen interns. She follows Cheol-Gyu to the parking lot and notices a crucial detail - his license plate number. This vital piece of information could be a major breakthrough, but unfortunately, she witnesses it as Im Sun, and her attempts to alert Byeong-Deok lack credibility.
The episode concludes on a high note, showcasing Ji-Ung's frustration after his boss throws a wrench into the investigation. Determined to find the truth, he enlists the help of Im Sun and Byeong-Deok to secretly investigate Cheol-Gyu's hospital.
Meanwhile, on the other side of the coin, Cheol-Gyu scrambles to his hospital upon learning of Im Sun's presence. A frantic chase ensues as he desperately tries to find her. Unaware of the danger lurking, Im Sun delves into Cheol-Gyu's office, searching for evidence. Just as Cheol-Gyu enters, assuming he will find her, a shocking twist is revealed. A nurse hands him Im Sun's blood results, and his expression contorts with disbelief. Her blood type is O positive, not A positive as he expected. Will this discovery unravel Mi-Jin's secret identity?
Episode 9 of Miss Night and Day masterfully weaves together romance, suspense, and a dash of mystery. The complex relationships between Mi-Jin, Ji-Ung, and Ko Won take center stage, while the investigation into the serial killings heats up. As the mystery thickens, one can't help but wonder if Cheol-Gyu has stumbled upon Mi-Jin's secret, and how this revelation will impact the lives of all involved.