The film opens with an unsettling image of bloodstains, leaving viewers to ponder the events that led to this moment. Emily Taylor, portrayed by Rooney Mara, faces a tumultuous period as her husband Martin (played by Channing Tatum) serves a four-year sentence for insider trading. Amidst their strained circumstances, she visits him in prison, receiving him with a mix of joy and disconnection, even when he expresses hopes of a better future with connections to a banker named Marshall Hellman.
That same night, within the confines of their middle-class home, a moment of intimacy unfolds, yet Emily's emotional disengagement is palpable. As Martin shares his dreams of success and wealth, Emily's lackluster response hints at her internal struggles. The next day, she heads to the parking lot where a crash against a concrete wall marks a desperate suicide attempt that raises alarm.
In another setting, Jonathan Banks, portrayed by Jude Law, finds himself navigating his role as a psychiatrist. After responding to a crisis involving a patient named Augustin, he is tasked with caring for Emily, who is recovering from her accident. Jonathan's concerns deepen as he prescribes her medications while emphasizing the need for therapy. Throughout her recovery, Emily grapples with her mental health, trying out various antidepressants, to no avail. Memories of her past, including her ambitions in graphic design and her romance with Martin, reveal layers of her character.
Desperate for answers, Jonathan reaches out to Emily's previous psychiatrist, Dr. Victoria Siebert (played by Catherine Zeta-Jones), who introduces him to a new medication, Ablixa. During a concert they attend, Emily's emotional state fluctuates, and a sense of foreboding looms as she is seen struggling internally. An alarming change occurs when, during a nightmarish episode, Emily fatally stabs Martin while sleepwalking, leading her directly into the heart of a murder investigation.
The subsequent trial reveals the complexities surrounding Emily's mental state and the tragic circumstances that led to Martin's death. As Jonathan takes on the role of her defense attorney, he grapples with mounting public scrutiny and implications of malpractice, while Emily finds herself pressured to plead insanity. The storyline exacerbates with a further examination of the relationships and choices that led to the crime. In a shocking twist, Jonathan uncovers a conspiracy involving Victoria, suggesting that Emily hadn’t been entirely truthful about her state or the suicide attempts.
The film escalates as Jonathan must protect his career while wrestling with the unraveling truth. Emily reveals their elaborate scheme, born from their shared desires for wealth and power, which included manipulating the pharmaceutical industry and feigning mental disorder symptoms. As the schemes come to light, the narrative pivots, pitting the two women—Emily and Victoria—against one another.
In the climactic conclusion, Emily's manipulations lead to her being pursued by law enforcement once her plans are laid bare. As she faces the consequences of her actions, Jonathan, having reclaimed some semblance of normalcy in his own life, watches as Emily is taken back into the mental institution, revealing how fragile the boundary between sanity and madness can be. The story concludes with Emily in her hospital room, displaying an eerie sense of calm despite the chaos surrounding her. Amidst all this, viewers are left with a haunting reflection on the nature of mental illness, manipulation, and the pursuit of wealth at any cost.
