A young and faith-filled nun, Cecilia, goes to an Italian convent, located in a picturesque area. The place is disturbingly beautiful, and the priests and nuns are unnaturally friendly. From the very beginning, Cecilia has the feeling that she didn't end up here by accident and that the true nature of this place is a closely guarded secret. When she discovers that she is pregnant and the doctor confirms the immaculate conception, the monastery begins to talk about a miracle. Cecilia has the impression that her pregnancy is no surprise to some priests, and the fear she sees in the eyes of the other nuns leads her to believe that there is some terrifying secret connected with this place. Strange rituals performed in the monastery, constant supervision under the guise of care, mysterious disappearances of young nuns and the constant feeling of someone's presence make Cecilia realize that she has been chosen to fulfill a mission that may lead to her destruction.