Rooney is Emily, who is anxious that her husband (Channing Tatum) is being released from prison after some creative insider trading. He quickly gets back into old habits which she wants to get away from, and it appears she has had depression in the past for a couple reasons. She tries to commit suicide, bringing her to the attention of a new doctor, Dr. Banks (Jude Law). He is sympathetic and tries to put her on different anti-depression medications, and goes so far as to speak to her old doctor, Dr. Siebert (Catherine Zeta Jones) about her past history, who mentions to him a new drug called Ablixa.
As is (probably) prevalent in the industry, a drug company approaches Dr. Banks and his colleagues to promote a different new drug. Dr. Banks takes this paid endorsement due to various financial needs but is open with his patients about his paid participation when he asks them to go on the test trials. The film shows one patient eagerly taking advantage of having a drug provided free.
Meanwhile, Emily mentions a friend has tried Ablixa with good results, so Dr. Banks, who has tried other drugs like Zoloft for her with no success, prescribes that for her. It is pretty successful in lightening her mood, but the side effects include bouts of sleepwalking where Emily acts out things and has no memory of doing so. During one of these bouts Emily does something tragic, which puts Dr. Banks' reputation in jeopardy. He is pressured to let Emily take the blame for a crime she has committed "due to reasons of insanity" rather than it become known that the drug he prescribed to her as the potential reason for her actions. Although he does sincerely want to help Emily, he bows to the pressure that he is getting from many sides and commits her to a mental health facility under his continued supervision, rather than send her outright to prison.
There are still a lot of gray areas of suspicion about him so Dr. Banks still wants to clear his reputation even though he is not legally blamed. During his own investigation he begins to suspect that Emily is not as innocent as he has been led to believe, and that there has been a conspiracy around him.
