Exorcism: Case Zero

You might have heard stories about it.
You might have read articles about it.
You might have watched movies about it.
But have you ever wonder what it would be like, if you have the chance to perform an exorcism yourself?

The year is 1998. Taking the role as Father Thomas Gates, you have been assigned to perform an exorcism ritual to a woman named Mary Kennedy, which was reported to have been possessed by evil spirit. Due to drastic deterioration of Mary's condition, you were contacted by her father to perform the exorcism a day in advance without any support from the church.