Holy Night is team that fights against groups that worships demons. The members of the Holy Night team are Bau (Ma Dong-Seok), Sharon (Seohyun) and Kim-kun (David Lee). Bau's special ability is his powerful physical strength. Sharon has an ability to identify demons and performs exorcisms. Kim-kun helps Bau and Sharon. Meanwhile, Psychiatrist Jung-won (Kyung Soo-Jin) visits the Holy Night team to save her younger sister Eun-seo (Jung Ji-So). A demon resides in Eunseo’s body.