A lawyer takes on a negligent homicide case involving a priest who performed an exorcism on a young girl.
When a younger girl called Emily Rose dies, everyone puts blame on the exorcism which was performed on her by Father Moore prior to her death. The priest is arrested on suspicion of murder. The trial begins with lawyer Erin Bruner representing Moore, but it is not going to be easy, as no one wants to believe what Father Moore says is true.
Plagued by horrific visions, and tormented by sinister manifestations of evil while at university, the troubled nineteen-year-old college student, Emily Rose, resorts to exorcism, only to die a horrible death. Now, her familys priest, Father Richard Moore, finds himself charged with negligent homicide, defended by the atheist lawyer, Erin Bruner. As a result, the Church presses Moore to get a plea bargain; however, he intends to give testimony, and call attention to the unseen dark forces that surround us. More and more, this trial becomes a battle between faith and science; nevertheless, what has happened to poor Emily?