8 timestamped notes explaining the Korean cultural context in this episode — customs, idioms, food, honorifics, and history, at the moment each appears on screen. These notes discuss events across the whole episode. To see them revealed scene-by-scene as you watch, use the episode page to find an airing.
Many private Korean schools are run by family-owned educational foundations, and the 이사장 (isajang), or foundation chairman, holds enormous behind-the-scenes authority. Having a parent or relative in that role meant near-total immunity from school rules — and, as the detectives are implying, from police scrutiny too.
The phrase '옷 벗어야 한다' literally means 'you'd have to take off your clothes,' but in Korean professional culture it's a fixed idiom for being forced to resign or fired. The senior officer is warning that going after a powerful family means losing your badge — a real and historically documented pressure on investigators in Korea.
The grandmother says her husband 'lived on alcohol' after their granddaughter vanished and died before her was found. Drinking to cope with unresolved grief is a widely recognized pattern in Korean society, and in dramas it signals a loss so total that normal life became impossible. The detail that he died before the truth came out deepens the tragedy.
Father Yoon's key observation is that a person fully possessed by an evil spirit — a 부마자 (bumaja) in Catholic exorcism terminology — would be unable to enter a consecrated church, kneel in prayer, or sit through the liturgy without showing distress. The fact that Park Hong-ju does all of this calmly suggests either she is not possessed, or something more unusual is happening.
Mi-jin describes Hong-ju as openly screaming at teachers and throwing things with no consequences — behaviour almost unthinkable under the strict Confucian-influenced hierarchy of Korean schools, where students are expected to bow and speak respectfully to every adult. The fact that even teachers could not stop her shows how completely her father's position as 이사장 (foundation chairman) shielded her.
Mi-jin says Hyeon-ju was hard of hearing and, partly because of that, had only one friend — her. In Korea of that era, students with disabilities were often quietly excluded from mainstream social life with little institutional support. The detail that her grandparents took her in after her parents divorced adds another layer: she had almost no safety net at all.
나눔의 손 means 'Hands of Sharing,' a fictional charitable foundation in the drama. The revelation that it also funds the psychiatric hospital where the key witness is held connects the dots: whoever controls the charity may have had eyes — and influence — over the witness for years, which would explain why he stayed silent and why his testimony was so easily suppressed.
Hwa-pyeong grabs Hong-ju to check whether one eye is sightless — the physical sign the show has established as proof that Bak Il-do is present. Korean shamanic and folk-horror tradition often marks spirit possession with a visible bodily change, and the drama uses this detail consistently across multiple possessed characters as its version of that sign.