When I Was You

Brienne Dougray is a 30-year-old woman living alone in her late grandparents' restored Queen Anne Victorian in Quinnesec Bluff, Iowa. Six months earlier, she was beaten, stabbed, and left for dead in an alley outside her insurance office. She survived but now has PTSD, OCD, stress-induced migraines, and memory loss from a traumatic brain injury. Her attacker was never identified, and her friends have dropped out of contact without explanation. Brienne's mother, Sonya, abandoned her at her grandparents' house when Brienne was eight. Her grandparents raised her and left her the house and a substantial fortune.

Brienne's only companion is her tenant, Niall Emberlin, whom she believes to be a surgical oncologist. He moved in shortly after her attack when friends insisted she not live alone. She considers him her sole friend and develops quiet romantic feelings for him, especially after learning he is separated from his wife, Kate.

Brienne's fragile stability shatters when she receives a monogrammed key from a local apartment complex. The manager tells her she signed a lease two weeks ago. Investigating, Brienne discovers a social media profile for another "Brienne Dougray," a woman who closely resembles her and works at a local PR agency. She visits the apartment, hides in a closet when the imposter arrives, and observes a woman who mirrors her appearance, mannerisms, and tastes.

Meanwhile, Brienne grows closer to Niall. In his study, she discovers a journal belonging to his estranged wife, Kate Emberlin, describing a lonely marriage. One evening Niall kisses her but pulls back, saying they should not rush things. After several failed attempts to confront the imposter, Brienne schedules an appointment at the PR agency under her middle name.

Before the meeting occurs, Niall bursts into the office, calls her "Kate," and rushes her out. At home, he presents documents including a driver's license bearing her photo under the name Kate Emberlin and psychiatric records from a now-defunct hospital. The records indicate that Kate has dissociative identity disorder, a condition in which alternate personalities take control of a person's consciousness, and that her alter identity is "Brienne Dougray." They state Kate was previously arrested for stalking the real Brienne Dougray, who dropped charges in exchange for Kate's voluntary committal. Niall insists Kate's memories of being Brienne are false. Unable to disprove his claims, Brienne agrees to seek treatment. Niall drives her to Crestview Psychiatric Center in South Dakota and commits her under a psychiatric advance directive, a document granting him authority over her care.

The novel's second part shifts to "Niall's" perspective and reveals a major twist. His real name is Shane Knudsen, and he is not a doctor but a patient transporter. He stole a cardiologist's badge and Photoshopped his own photo onto it to impersonate a physician. Shane's stepmother was Sonya, Brienne's biological mother, who was raised by the Dougrays but disowned after poor life decisions. Before dying of pancreatic cancer, Sonya told Shane about her parents' fortune and expressed her wish that he could live without worry. Shane decided to steal Brienne's inheritance, viewing it as rightfully owed to Sonya.

Shane was at the hospital when Brienne was brought in after her assault. He accessed her records, learned she needed a roommate, and answered her ad with fake credentials. He then isolated her systematically: He spoofed her phone number to send fabricated nude photos to her friend Marisol Valdes's husband, causing their separation, and changed the numbers in Brienne's phone so she could never reach her friends. The "other Brienne" is Shane's girlfriend, Sam Tucker. Shane gave Sam the identity and wardrobe, telling her it was an alias to help her find work since her criminal record made her unhirable. Sam has no knowledge of the larger scheme. Shane fabricated all the Kate Emberlin evidence, including the diary, medical records, and identity documents.

While Brienne is at Crestview, Shane accesses her financial accounts, discovers her portfolio is worth over 13 million dollars, and begins draining the funds. Brienne reads Kate's diary obsessively but feels no connection to Kate's life. She notices the wedding ring Shane brought her is fake: The white gold has worn to reveal yellow beneath. She confesses to Dr. Schneider, the facility's psychiatrist, that she faked being Kate and raises questions about her supposed husband's behavior. Dr. Schneider acknowledges the diagnosis is falling apart, especially since the defunct hospital has no record of Kate Emberlin. Brienne submits a three-day letter, a formal patient request that initiates a discharge review, and the board approves her release without notifying Shane.

Brienne drives home and discovers signs of another woman in the house. An urgent email from her accountant reveals her entire retirement portfolio has been cashed out. She visits the hospital and meets the real Dr. Niall Emberlin, an elderly cardiologist nothing like the man in her house. She visits Marisol, demonstrates that someone altered the phone numbers in Brienne's contacts, and enlists Marisol's help.

Brienne returns home and pretends to still be Kate while Shane pretends to be overjoyed. Brienne freezes her remaining accounts. Shane, meanwhile, laces Brienne's milk, creamer, and mouthwash with antifreeze and steals a syringe of potassium chloride, a drug that can stop a heart, from the hospital. Brienne, suspicious of tampering, avoids consuming anything in the house.

Sam grows uneasy, drives past the house Shane claimed belongs to an elderly client, and sees Brienne through the windows. After encountering Brienne by chance at a shopping center, the two piece together Shane's scheme. Sam reveals his real name and confirms his stepmother was Sonya. Brienne realizes Shane targeted her to avenge Sonya, who believed the Dougrays replaced her with their granddaughter.

Brienne files a police report with Detective Baker. He says the evidence is insufficient for an immediate warrant but confirms that DNA from her original assault matches a man in prison, proving the attack was unrelated to Shane. Worried about Sam, who intends to say goodbye to Shane, Brienne borrows a handgun from Marisol and drives home. She finds Shane gripping Sam upstairs beside a half-packed duffel bag and orders him at gunpoint to let her go. She tells Shane that Sonya wrote Brienne hundreds of letters over the years and never once mentioned him, suggesting Sonya manipulated him the same way he manipulated Brienne. As she retrieves the letters, she dials 911. Sam attacks Shane from behind, and in the struggle, Shane flings Brienne down the stairs.

Shane grabs the gun and flees with Sam. He is pulled over for running a red light by a coworker who moonlights as a reserve police officer. While the officer runs Shane's fake ID, Sam climbs out and gets into the cruiser. Shane speeds away but is apprehended after police deploy spike strips.

Brienne wakes in the hospital with cracked ribs and a concussion. Police find a loaded syringe of potassium chloride on Shane and antifreeze-contaminated items throughout the house, adding evidence of attempted murder to his charges. Sam leaves Brienne a letter of apology and returns her grandmother's opal ring, which Shane had given Sam. Three months later, Brienne has sold the Queen Anne, reconnected with her friends, and recovered about half the stolen funds. She gives Sam a moonstone ring symbolizing new beginnings and prepares to leave Quinnesec Bluff, determined to reclaim her life.