Doctor Ava Knowle is a psychiatrist working with the mentally ill, helping them on the road to recovery so they can leave the hospital and continue to live their lives independently. When a new patient, Alex Hurd, arrives on the back of a gruesome, violent crime, it is up to Ava to assess Alex and decide if he should be treated in the hospital or face prison. Upon meeting Alex, Ava knows she is facing the biggest challenge of her career. But the danger he poses becomes even more evident when he violently murders Ava's colleagues and kidnaps her. Ava finds herself fighting for her life as Alex reveals he is a scientist and begins to perform torturous experiments on her. When she realises escape is out of the question, Ava decides she must convince Alex to turn his experiments on himself. It is his life or hers and the outcome will cost everything.