Every Last Fear

The novel opens with the discovery of four bodies in a vacation rental in Tulum, Mexico. A father, mother, teenage girl, and young boy are found dead two days after missing their return flight. A gas leak appears to be the cause, but on the patio, investigators find a trail of blood and the father's remains, badly mutilated by wild dogs.

Matt Pine, a 21-year-old NYU film student, is playing chess in Washington Square Park when he learns FBI agents are waiting at his dorm. Special Agent Sarah Keller delivers the news: Matt's parents, Evan and Olivia Pine, and his siblings, 17-year-old Maggie and six-year-old Tommy, are dead. The media descends because Matt's older brother, Danny Pine, is the subject of a Netflix documentary called A Violent Nature, which argued Danny was wrongfully convicted of murdering his girlfriend, Charlotte Rose, in their hometown of Adair, Nebraska. Keller escorts Matt to Fishkill Correctional to break the news. Danny is devastated and tells Matt not to come back. Matt reflects on the last time he saw Danny free: the night Charlotte was killed, when a 14-year-old Matt glimpsed a dark figure in a letterman jacket pushing a wheelbarrow toward the creek near their house.

The narrative alternates between present-day investigation and flashback chapters labeled "BEFORE." Evan is in crisis. Fired from his accounting firm, Marconi LLP, and hiding severe financial ruin from Olivia, he attempts suicide by swallowing pills and Scotch. A FaceTime call interrupts him: A young woman who looks like Charlotte says "Help me" before the call cuts off. The caller ID traces to the Moloko Bar in Tulum. Evan forces himself to vomit up the pills and becomes consumed with the possibility that Charlotte is alive.

Maggie emerges as the family's tireless investigative force, running social media for the Free Danny Pine campaign. She receives an anonymous tip: a cell phone video from the night of the party where Charlotte was last seen, which may show the Unknown Partygoer, a key unidentified figure from the documentary. Her classmate Toby Lee demonstrates deepfake technology, proving the FaceTime call could have been fabricated. Maggie traces the phone that called her father to two locations in Tulum. Despite her skepticism, Evan plans a last-minute family trip to Mexico. Maggie's investigation is nearly derailed when a classmate, Eric Hutchinson, sexually assaults her at a party and retaliates with cyberbullying.

In parallel flashbacks, Olivia travels to Adair to manage her father's worsening Alzheimer's and reconnects with Noah Brawn, her high school boyfriend and the state's lieutenant governor, who is about to become governor. The novel reveals that Olivia had a month-long affair with Noah around the time of Charlotte's murder and that Tommy may be Noah's biological son. The widow of Ron Sampson, a detective who worked Danny's case and later died under suspicious circumstances, gives Olivia blood work and evidence logs, insisting Sampson was murdered before he could reveal proof of Danny's innocence.

Keller's investigation deepens. The filmmakers behind A Violent Nature, Judy and Ira Adler, bring her crime scene photos showing Olivia's book positioned upside down, suggesting staging, and fingerprint bruises on Maggie's wrists. All family devices have been professionally wiped. Keller discovers Evan's deleted searches about suicide and learns Marconi LLP is under investigation for laundering money for the Sinaloa Cartel. She raids the firm but concludes it had nothing to do with the deaths.

Matt flies to Mexico to claim the remains, but the trip turns dangerous. Before his flight, a man with a cleft lip scar shoves him into traffic, patting him down as if searching for something. In Tulum, a young woman calling herself Hank, who has been hired to lure Matt, befriends him at a bar, but on a dark road she discovers a newspaper with his family's photo, panics, returns his stolen phone, and screams at him to run. Matt flees into the jungle. The next day, consular officer Carlita Escobar extracts him from a hostile encounter with local police and informs him the remains have been shipped to Nebraska.

The "BEFORE" chapters detail the family's time in Mexico. Evan sneaks out alone to the Moloko Bar, where a bartender confirms he recognizes Charlotte's photo. Maggie convinces her father not to return by revealing phone-tracking data showing a second address. They leave a note at the address and follow the man who emerges to the bar, where Maggie photographs him with a woman. During a walk, Maggie tells Olivia about the assault. That evening, Evan examines blood work from Sampson's file and discovers the sample labeled as Danny's is type O negative, which is impossible given Evan's type AB blood. He already knew from Tommy's emergency surgery that he could not be Tommy's biological father. Evan deduces that Sampson switched Danny's sample with that of Kyle Brawn, Noah's son, meaning Kyle fathered Charlotte's baby. Evan tells his family they have proof to free Danny.

That same night, a contract killer known as "the Lip," the man with the cleft lip scar, poisons the family through their water bottles. He stages the scene and wipes all devices. In her final conscious moments, Maggie sends Matt the photograph of the Lip and the woman. Evan, partially conscious, stabs the Lip with a pen; the enraged killer drags Evan outside, covers him in food, and opens the patio gate to attract wild dogs.

Matt travels to Adair for the funeral. Keller shows him Maggie's photo, and Matt recognizes both figures: the woman from Mexico and the man who attacked him in New York. After the funeral, Jessica Wheeler, Matt's childhood friend who runs the local bar, reveals she sent the anonymous party video. Her brother Ricky, who has a brain injury and is consumed by guilt, had drunkenly confessed that the video contained hidden proof. Matt re-watches the video and realizes the dark figure he saw as a child was not Danny but Kyle Brawn, wearing Danny's letterman jacket. Around the same time, Danny is brutally attacked in prison.

Keller meets with Neal Flanagan, a fixer for Nebraska's disgraced former governor who once offered Danny a pardon for one million dollars. Flanagan confirms someone used his encrypted phone line to hire the Lip to kill Evan, with payment delivered through a drop at the statehouse. The information leads to Noah Brawn.

Matt confronts Kyle at the governor's mansion. Kyle confesses that Charlotte's death was an accident: He pushed her after she revealed that Noah, not Kyle, had fathered her baby. Kyle and Ricky Wheeler moved the body, intending to frame a serial killer known as the Smasher, never intending for Danny to be blamed. Noah enters with a gun and reveals his full involvement: He crushed Charlotte's skull to mimic the Smasher's methods, orchestrated the blood switch, and hired the Lip when Maggie's investigation threatened to expose the truth. Kyle, horrified that his father ordered the murders, confronts Noah. In the struggle, Kyle is fatally shot. Noah aims at Matt, but Matt tackles him. Keller and police arrive as Matt raises a marble bookend over Noah's head. Keller talks him down, and Matt hurls the bookend at the floor.

In the epilogue, Danny has been pardoned and freed. Noah is imprisoned at the facility where Danny was first held. Matt is making a short film in Washington Square Park with Danny at his side. The brothers sit at a café where their family once gathered to watch Manhattanhenge, the biannual event in which the setting sun aligns with Manhattan's street grid. Kala, one of Matt's college friends, arrives and takes his hand. In a final scene, Keller leads a tactical team in Colombia to capture the Lip, tracking him through airline records.