She's standing at the front door. Covered in blood. Is she the victim of a crime? Or the perpetrator? A teenage girl -- Sienna, a troubled friend of his daughter -- comes to Joe O'Loughlin's door one night. She is terrorized, incoherent, and covered in blood. The police find Sienna's father, a celebrated former cop, murdered in the home he shared with Sienna. Tests confirm that it's his blood on Sienna. She says she remembers nothing. Joe O'Loughlin...