[Machine Translation] No.1 hit in its first appearance in Japan! A horrifying occult thriller where taboo and fear intersect! Song Hye-kyo & Jung Yo-bin! Top actresses of talent! Hee-jung (Moon Woo-jin), a young boy suffering from unexplained seizures, is called the "Black Nun". Sister Yunia (Song Hye-kyo), known as the "Black Nun," claims that his symptoms are the work of the evil "Twelve Demons" and demands that he undergo an exorcism. However, Father Park, the doctor in charge of the patient, dismisses the claim, saying that there is no such thing as demonic possession and that it is merely a combination of multiple mental illnesses. Neither medication nor psychotherapy has shown any effect, and Hee-joon's symptoms worsen day by day. Yunia, driven into a corner, decides to perform an exorcism ritual herself. However, the church strictly forbids the ritual to be performed by an unordained nun, a "taboo of faith. Even so, in order to save him, Yunia decides to go through with the forbidden ritual with the involvement of Father Park's disciple, Michaela (Jung Yo-Bin). From that moment on, something unexplainable begins to stir quietly around them. The trailer is included as a bonus video.