Heather

The novel opens with a second-person prologue: A woman gives birth to a daughter while her husband, Ben, is on the phone across the room. The doctor notices an old scar on her body and glances meaningfully at Ben, but she refuses to acknowledge the question. She names the baby Blair, hoping a name rooted in Ben's stable family will give her daughter an inheritance unlike her own: a history of women who disappear.

In September 2023, Callie Hauser patrols Pine Lakes, a small town in the New Jersey Pine Barrens, a vast stretch of remote forested land. Callie is the town's first female Chief of Police, having left a narcotics career to care for her best friend, Jane, who was severely injured in a hit-and-run. Retired former chief Frank Caputo, Jane's father-in-law, recommended Callie, but the all-male squad resents her. Her primary challenge is a heroin ring distributing drugs in green glassine bags stamped with pine boughs, fueling fatal overdoses.

One night Callie pulls over a swerving car and discovers the driver is her estranged mother, Jenna, barefoot and drunk. At the station, she overhears officers reveal something she never knew: As a teenager, Jenna found a dead newborn on the roadside, and the case went cold. Callie demands the Baby Doe files and resolves to reopen the investigation. Jenna refuses to discuss it, calling Callie's career as a cop "the shame of my life" (16). The case file is thin: The baby died of exposure, born alive but only hours old, and a broken amber bead bracelet found near the body suggests someone else was present. Callie contacts Benny Healey, a colleague working cold cases, who agrees to search for usable DNA.

Visiting Jenna's house, Callie finds it unexpectedly clean, with a three-month Alcoholics Anonymous (AA) sobriety chip on the table and a clipping about Callie's appointment on the refrigerator. Then Jenna's purse turns up on a hiking trail with a green drug bag inside. Jenna has vanished.

A second timeline, narrated in second person, follows Annabelle Riley in 1990 and 1991. Annabelle and her twin sister, Sabrina, are teenagers living alone in a decaying Pine Barrens house after their mother abandoned them. Sabrina has been seeing an older man she calls the Coyote. When he mistakes Annabelle for Sabrina, Annabelle deliberately gets in his car, wanting to understand what her sister has been keeping from her. He drives to a clearing near a sinkhole, and she loses her virginity in a painful encounter; afterward, he reveals he knew she was not Sabrina. The betrayal fractures the sisters' bond. A violent fight leaves Annabelle with a deep cut on her arm that Sabrina stitches shut using fishing line and a needle sterilized in the Coyote's silver Zippo lighter.

Annabelle realizes she is pregnant but cannot get help: A crisis pregnancy center she contacts steals her savings and lectures her about sin instead of providing care. Sabrina discovers the pregnancy and begins preparing birthing supplies while planning to confront the Coyote with blackmail, threatening to expose his relationships with multiple underage girls. On the evening of March 1, 1991, Sabrina leaves to meet him and does not return. Annabelle labors alone and gives birth near old factory ruins behind their house. The baby is motionless. She carries the infant to the roadside, hoping someone will find them. On the ground she spots Sabrina's broken amber bracelet and understands her sister will not come. She sets the baby in the grass, takes a single bead, and walks away, eventually building a new life under the name Iris Owens.

Back in 2023, Callie pursues leads. She confronts Billy Fauver, a local man with a history of violence who clashed with Sabrina at the bait shop where Sabrina worked. Fauver directs her to Trent Brentwood, a local man who once had a casual romantic relationship with Sabrina, who reveals a critical detail: Sabrina had a twin named Annabelle, quiet and smart, with a scar on her arm. Callie also saves a teenage girl named Layla Hart from a heroin overdose using Narcan, an overdose-reversal medication. Layla works at Eden Grows, a plant nursery run by Luke Caputo, the older brother of Jane's husband, Damien. During this period, Callie begins a relationship with Adrian, a marine biology professor.

Healey calls with shattering DNA results: Callie is a genetic half-sibling match to Baby Doe on the paternal side. They share the same unknown father. Meanwhile, a third timeline follows Blair, Iris Owens's 18-year-old daughter, who discovers a hidden duffel bag in her mother's closet containing the Coyote's lighter, photographs of two nearly identical girls, and a note in unfamiliar handwriting. Blair orders a genetic testing kit hoping to find her mother's lost twin, but her submission matches to Baby Doe through public databases. Annabelle is arrested after a genetic genealogist posts a viral video, exposing her real identity to the world.

Before the arrest, Callie visits Annabelle in Cortlandt, New York, having found a note Annabelle left at the old Riley property years ago in case Sabrina came looking for her. Annabelle confirms she was the one who had been pregnant and that Sabrina disappeared the night before the birth. She gives Callie Sabrina's notebook and the lighter as evidence. Separately, Callie confronts Jane about a green drug bag that Opal, Jane and Damien's young daughter, found in Damien's truck. Jane confesses that she and Damien sold hallucinogenic mushrooms during COVID, then brought in Fauver as a distributor. Fauver escalated to heroin and fentanyl, and when they tried to cut ties, he arranged Jane's hit-and-run.

The climax arrives when Frank calls Callie to a scene near a sinkhole in the woods. She finds Damien instead. He reveals that his brother Luke was a former police officer forced out for violence and for using his position to prey on underage girls. Callie realizes Luke is the Coyote and her biological father. Damien confesses to killing Sabrina at this sinkhole as a teenager to protect Luke, then attacks Callie and drags her toward the water. Jane arrives with a rifle and shoots Damien in the leg. State police arrest him for murder and attempted murder; Frank is charged as an accessory.

Callie hikes deep into the Pine Barrens and finds Jenna alive in Hauser Hollow, an ancestral hunting cabin. Jenna reveals that Luke groomed her when she was 15 and raped her, resulting in Callie's conception. When Jenna tried to report him the morning she found Baby Doe, Frank threatened to make her the suspect.

Annabelle stands trial and is acquitted of first-degree murder but convicted of involuntary manslaughter, receiving one year in prison and two years' probation. Blair testifies about her mother's character. A journalist publishes an exposé in the New York Times detailing Luke's predatory history; nine women come forward, and Luke is arrested.

Callie and Adrian plan a small wedding; she is pregnant and enrolled in law school. In the final chapter, Annabelle, now asking to go by Anna, returns to the Pine Barrens with her family. Two headstones stand at the factory ruins: one for Sabrina, whose body divers recovered from the sinkhole, and one for Baby Doe, whom Annabelle has named Heather after the Pine Barrens wildflower her mother loved. She buries the single amber bead she has carried for over 30 years in the earth between them.