In 1988, the abusive and deranged principal of a Catholic Boarding School, Nun Ursula, attempts to 'purify' a pregnant girl with water, almost killing her. Her class and dorm mates Joanna, Christine, Eulalia, Zoe and Susan fight with the nun and drown her in a bathtub. The six teenagers dump her body in a lake with holy water and make a pact of silence. Eighteen years later, the spirit of the nun is released from the lake and possesses Eve, the daughter of one of Nun Ursula's killers. In Eve's body the Nun seeks revenge against her former students.
