Under the direction of her husband, the chief administrator of the psychiatric ward at the Woodward Penitentiary for Women, Dr. Miranda Grey treats dangerously disturbed patients like Chloe, an intensely charismatic murderess whose confessions of satanic torture are dismissed by the judicious doctor as the psychotic meanderings of a paranoid mind.

When Miranda awakens from a horrific incident, she is shocked to discover that her husband has been murdered and the bloody evidence points directly at her. Unable to fathom having committed and unmotivated act of such sheer brutality against a man she loved and admired, Miranda suddenly find herself confined to Woodward alongside the highly unstable patients she used to treat with methodical detachment.

Forced to rely on her instincts rather than facts, Miranda begins to believe that she has been possessed by a supernatural force determined to exact revenge at the expense of her sanity. As Chloe draws her deeper into her own personal hell, Miranda must determine if she is being driven to madness... or closer to the truth.

Synopsis from official site.