When a devil-worshipping criminal network plunges Seoul into chaos, the police turn to Holy Night—a trio of supernatural demon hunters—to restore order and defeat the rising evil.

Dae-guk, a nosy man from Apgujeong, and Ji-woo, a cold but skillful plastic surgeon, open a plastic surgery business in Gangnam. Dae-guk is an unemployed man who likes to pry into other people’s businesses.

Soo-hyun, a fourth-year elementary school teacher, is about to get married. One day, Yohan, a student in her class, comes to Soohyun, who was busy and happy. Yohan confesses to Soohyun that he is experiencing domestic abuse. But the next day, John's lies await Soohyun.

Hye-jeong, who lost her husband in an industrial accident, moves into a sparky new town apartment 'Dream Palace'. But things go awry, construction defect occurs in her unit, and to catch up the repairment fee, she joins the discount promotion act of the apartment. But her neighbors ostracize her for devaluing the apartment, and to protect the unit she purchased as the exchange on her husband’s life, she dives into the demo once more.

Sumin avoids the holidays by staying at her divorced brother Sangchul's house. Unexpectedly, their mother Soonja arrives, announcing her plans to live independently. Soon after, Sangchul's ex-wife Hyunsook also shows up. With these unexpected guests, tensions rise as they awkwardly spend the holiday together.