| Director | Michael Mohan |
|---|---|
| Genre | horror film, psychological horror film |
| Runtime | 89 min |
| Country | Italy, United States |
| Budget | $9 million |
| Box office | $35 million |
Sister Mary sneaks into a superior's bedroom at night and steals keys to escape through the locked gates of a Catholic convent. Four hooded figures capture her and break her leg, then knock her unconscious. Mary later wakes up in a coffin and is buried alive.
After surviving a drowning in a frozen lake and being declared dead for seven minutes, young novice Sister Cecilia, who turned to Christianity at an early age, becomes convinced God had saved her for a purpose. She receives an invitation from Father Sal Tedeschi to join a convent in Italy that tends to dying nuns. Cecilia becomes a nun.
Cecilia befriends Sister Gwen and is struck by certain oddities, such as an elder nun having cross-shaped scars on the soles of her feet. The convent's chapel houses a relic, a Holy Nail that was used to crucify Jesus. After having nightmares of hooded figures, Cecilia is shocked to learn that she is pregnant, even though she is a virgin. The convent's inhabitants begin to treat her as the next Virgin Mary, with many proclaiming the child is a "blessing".
Another nun, Sister Isabelle, tries to drown Cecilia out of jealousy and later dies by suicide. Cecilia throws up one of her own teeth and her health worsens. Her request to be taken to a proper hospital is denied by Father Tedeschi. Gwen publicly chastises the convent superiors for this abnormality but is then taken away by Father Tedeschi and Deacon Enzo. At night, Cecilia sneaks around the convent and finds her personal file, and is shocked to find information about her childhood accident and a karyotype. Hearing a woman screaming, she investigates and is horrified to witness a hooded figure cutting out Gwen's tongue. An elder nun appears and silences Cecilia. She begs to escape, but the elder chastises her, saying that she will never leave the convent.
Cecilia fakes a miscarriage to be taken to the hospital, but the deception is exposed and she is tied up. Tedeschi explains that he was a geneticist before becoming a priest and used DNA samples taken from the Holy Nail to impregnate nuns in the hopes of ushering in a new messiah. Before Cecilia, Tedeschi's numerous attempts failed, often resulting in malformed fetuses. Tedeschi brands a cross into Cecilia's feet, as seen in other nuns.
Cecilia makes another attempt to escape. She beats Mother Superior to death using a crucifix, and shortly afterward, her water breaks. She manages to strangle the cardinal with her rosary before dousing Tedeschi's lab in ethanol. Tedeschi arrives and tries to stop her, but Cecilia narrowly escapes by igniting the ethanol with a lighter.
Tedeschi breaks out of the laboratory after extinguishing the flames and continues his pursuit of Cecilia, forcing her to flee into the catacombs under the convent. Cecilia finds Gwen's mutilated corpse along with a hole in the catacomb's walls. Tedeschi finds her just as she is about to escape and a struggle ensues. Tedeschi tries to cut Cecilia's stomach open, but she stabs him in the throat with the Holy Nail relic, which she had previously stolen from the chapel. After exiting the catacombs, Cecilia agonizingly gives birth and bites through the umbilical cord herself. She is horrified by the sight of the baby, which is heard making strange, animalistic noises. Cecilia stumbles away to grab and lift a nearby rock, which she uses to crush it to death.}}