Sung Dong-Il and Jin Hee-Kyung are a married couple. They run a boarding house near an airport and most of their guests work at the airport.

Yeong-ho completely dominates Gi-tae and his gangmates. After hearing what happened, an 11th-grader offers him the spot, but Yeong-ho refuses. Meanwhile, Dae-chun who was suspended for school bullying is back and he’s been keeping a low profile.

Seoul, South Korea, 1997. When the young but extremely anxious student Jin-seok, his parents and his successful older brother Yoo-seok move to a new home, mysterious and frightening events begin to happen around them, unexplained events that threaten to ruin their seemingly happy lives. Unable to understand what is happening, Jin-seok wonders if he is losing his mind.

Major crimes unit detective Seong-jin arrests Tae-sung for petty crimes, but shocked to find out that he is the notorious serial killer. However, Seong-jin becomes doubtful of his identity as the serial murder case is investigated.