Fifteen year-old Emma Evans has an argument with her mother Lucy since she wants to go to a concert in London with her friends Rose and Alex. Emma immediately has a convulsion and her family takes her to the hospital, but the doctors do not find any physical problem. Then her father John tries to convince his wife to send Emma to school, instead of homeschooling, but she prefers to keep Emma in the family-based education. Lucy sends her daughter to the psychoanalyst believing that she has psychological problems and Emma asks her friend Rose to record her session of hypnosis though the cellular but the doctor dies during the session. When Emma listens to the tape, she believes she is possessed by the devil and asks her parents to be submitted to an exorcism with her uncle, Priest Christopher Taylor. However her skeptical mother is against the ritual and recalls that Chris was responsible for the death of a teenager...

The successful American writer and atheist Joseph Crone participates in a support group to accept the death of his beloved wife Sarah and their son Diogo. Joe befriends Sadie in one of the meetings and she helps him when he has a car accident. When Joe's estranged religious brother Samuel Crone (Michael Landes) tells him that their father is terminal, he travels to Barcelona to stay near the death bed of his father. Joe has visions of demons and with the number 11 and he finds that something evil will happen with Samuel and him on 11 November 2011.