When Emily Taylor (Rooney Mara) is admitted to ambitious psychiatrist Dr. Jonathan Banks (Jude Law) after a suicide attempt, he does everything he can to help his new patient. Emily's husband Martin (Channing Tatum) has just been released from prison after serving several years for insider trading. But their attempt to start a new life together after the long, painful separation fails: Drugged up, Emily kills her husband, but can't remember anything the next morning. Now it's up to Dr. Banks to prove that his patient didn't know what she was doing because of the drugs she was taking...