First Born

The narrator introduces herself as Molly Raven, a 22-year-old woman living alone in Camden Town, London. She describes herself as "half a person," the darker and lesser half of a monozygotic (identical) twin pair. Molly is obsessively risk-averse, testing her fire alarm repeatedly and keeping fire extinguishers in every room. She contrasts herself with her twin, Katie (whom she calls KT), describing KT as prettier, funnier, and carefree. A year earlier, KT moved to New York to attend Columbia University on a generous private sponsorship, devastating Molly. Their parents, Paul and Elizabeth Raven, are a modest couple from outside Nottingham, and their father's business is struggling financially.

Molly receives a phone call from her distraught parents in New York. Her father tells her KT is dead, found in her apartment looking peaceful, as if asleep. Despite her terror of flying, Molly books a flight to JFK, purchasing two travel insurance policies and obtaining an ESTA visa waiver, a travel authorization required for British citizens entering the United States.

In New York, Molly reunites with her parents at the Bedfordshire Midtown Hostel. The reunion is painful; her mother sees KT's face in Molly's identical features. Her father reveals the family believes Katie was murdered, though the police are not yet saying anything definitive. There was no forced entry, no blood, and no signs of struggle. That night, Molly overhears her mother whisper through the thin walls: "We have to tell her the truth, Paul."

At the 26th Precinct, Detective Martinez, the lead investigator, interviews the family. Molly identifies KT's boyfriend, Scott Sbarra, and her best friend, Violet Roseberry. Martinez reveals bruising on KT's face and mentions she recently took out a life insurance policy. When Molly presses her parents about the overheard remark, her father admits the family business has collapsed entirely.

The family visits KT's apartment, where they meet Victoria Bagby, the landlady, and her son Shawn, who lives in the basement and runs a YouTube channel. A photo collage includes pictures of KT with Scott, with Violet, and with an unidentified young man wearing an "End Chad" T-shirt, a phrase connected to incel culture, an online subculture of men who blame women for their inability to find romantic partners. Molly notices a separate Polaroid of Shawn and KT together and questions him, but he dismisses the relationship.

Molly investigates on her own. At the Columbia boathouse in Inwood, Scott is shaken by her resemblance to KT. He mentions tension between KT and Professor Eugene Groot and describes Shawn as "a creep." A man calling himself Bogart DeLuca then approaches Molly, claiming to be a private investigator hired by a Columbia-affiliated foundation. Molly names four suspects: Scott, Shawn, Violet, and Groot.

Using the twins' childhood secret language, Molly hacks into KT's encrypted FortressMail account. She finds an unsent draft describing someone called "V," likely Violet, as obsessive and traces the recipient address to Groot's office at Columbia. She meets Violet, who confirms Groot had a full affair with KT that ended when he refused to leave his wife. Molly then dines with Groot at the Harvard Club. He denies intimacy with KT but describes Shawn as "dangerously obsessed" and reveals KT's sponsorship came from a private foundation unrelated to Columbia. As the evening progresses, Groot grows inappropriately flirtatious with Molly.

Working through the night, Molly traces KT's social media and discovers repeated location overlaps with James Kandee, a wealthy British philanthropist. She connects Kandee to the Turbach Foundation, the likely entity behind KT's sponsorship. Cross-referencing flight records, she discovers Kandee's private jet flew from London to Teterboro, a New Jersey airport, on the day of KT's murder and returned the same night.

The family learns the autopsy results: KT died from homicidal asphyxiation, smothered with a pillow. Fibers were found in her eyelids and mouth, and bruising indicates she was pinned down. The police believe the killer was someone KT trusted. Molly contacts Martinez with her findings about Kandee. DeLuca, meanwhile, reveals that Shawn formerly posted misogynistic content online, including fantasies about killing, and that Groot has no alibi for the night of the murder. When Molly mentions DeLuca to Martinez, however, the detective reveals no private investigator by that name is licensed anywhere in the United States and warns that DeLuca could be the killer.

The family holds a cremation at Fresh Pond Crematory near Brooklyn. Molly places her palm on the cardboard box containing KT's body and whispers goodbye. In a shocking first-person confession, the narrator states: "And I feel sorry for holding the pillow over her face until she stopped struggling" (180). The person narrating as the grieving twin is the killer.

After her parents depart with the ashes, Molly stays in New York. The narrative voice shifts as she reveals her true nature. KT's secret decision to attend Columbia, after promising Molly she would study at University College London, triggered 14 months of meticulous planning. Molly discovered Kandee was behind the sponsorship, confronted him at his London townhouse disguised as KT, and blackmailed him into flying her to New York hidden in a reinforced suitcase in his jet's cargo hold. In the apartment, the twins reconciled over tea. Molly suggested a power nap, and when KT fell asleep, Molly smothered her with a pillow. She flew back to London that night and later arrived on a commercial flight to establish her alibi.

Operating from a secret suite at the Ritz-Carlton arranged by Kandee's organization, Molly launches retribution against those who wronged KT. She plants fabricated Polaroid evidence at Groot's Connecticut home, destroying his marriage. She creates a viral YouTube video exposing Shawn's incel past. On Halloween night, she lures Scott to a hotel room and murders him, having established an alibi at a nearby cinema screening of The Shining.

Scott's body is discovered sooner than expected. Martinez questions Molly and reveals the police suspect a connected vendetta targeting people in KT's circle. Her scheme unravels further when DeLuca warns that the Polaroid she planted at Groot's house contains an anachronistic detail: A jack-o'-lantern in the background was carved after KT's death, proving the woman in the photo was an impersonator. DeLuca arranges an emergency extraction, warning that Kandee's organization will threaten her parents if she fails to appear.

On marathon day, Molly evades police through Manhattan, dons a latex old-man mask, and walks past Martinez on the street unrecognized. She is driven to New Jersey and loaded into a leather dog crate designed for one of Kandee's Bernese mountain dogs. At Teterboro airport, a customs official scans a fur patch held to the crate's hatch; the microchip beeps, matching the dog's registered identity. The crate is loaded onto Kandee's Gulfstream jet.

Airborne, Kandee opens the crate. The narrator wets her sleeve and wipes her eyebrow, smudging concealer to reveal a scar. Holding a novelty lighter shaped like a revolver, she declares: "Katie. My name is Katie" (348). In the novel's final twist, the narrator has been Katie all along. She explains that in the apartment, she sensed something was wrong and only pretended to sleep. When Molly crept toward the bed with a pillow, Katie, a swimmer with superior upper-body strength, overpowered and smothered her instead. Katie plucked hair from Molly's eyebrow to recreate the appearance of her own distinctive scar, arranged the scene, and entered the United States using Molly's unused passport, impersonating her anxious twin throughout the investigation.

Katie forces Kandee into the dog crate, takes his cash and vintage Rolex, and walks off the jet at their tropical destination disguised as him. She envisions bringing her parents to live with her, free from debt and the lifelong demands of caring for Molly. The novel closes with her vision of a "perfect family": "Three Ravens. No extras. No duplicates" (358).