In mid-September, eight strangers across the United States each receive an anonymous letter containing nothing but a typed list of nine names, including their own. A ninth recipient, Jack Radebaugh, receives his copy weeks later after it is forwarded from his old address. None of the recipients recognizes the other names, and most dismiss the letter as junk mail or a computer error. The novel follows these nine people as they react to the list, develop theories about its meaning, and, one by one, begin to die.
The recipients include Alison Horne, a woman in New York City supported by her married lover, Jonathan Grant; Arthur Kruse, an oncology nurse in Massachusetts grieving his husband's death; Ethan Dart, a singer-songwriter in Austin, Texas; Jessica Winslow, an agent at the Federal Bureau of Investigation (FBI) field office in Albany, New York; Caroline Geddes, an English professor at the University of Michigan; Jay Coates, a struggling actor in Los Angeles who harbors violent fantasies about harming women; Matthew Beaumont, a suburban father in Massachusetts; Frank Hopkins, the elderly owner of the Windward Resort in Kennewick, Maine; and Jack Radebaugh, a retired businessman in West Hartford, Connecticut, estranged from his wife.
Frank Hopkins is the first to die. During his usual morning beach walk, he finds an unstamped envelope on the stone jetty he always touches before turning back. As he reads the list, someone grabs him from behind, forces him facedown into a shallow tide pool, and drowns him. Detective Sam Hamilton of the Kennewick Police Department, who has known Frank for years, suspects foul play after noticing that Frank's head appears to have been pushed deep into the sand. A crumpled copy of the list is found in Frank's hand.
At the FBI office, Jessica's supervisor, Aaron Berlin, informs her that Frank Hopkins has been murdered and that an identical list was found at the crime scene. Jessica begins contacting the other recipients, reaching Ethan, Arthur, Caroline, and Matthew by phone. None recognizes any of the other names. Jessica notices a possible personal connection: Her father, Gary Winslow, once mentioned a friend named Art Kruse, and Arthur confirms that his estranged father shares that name. Jessica cannot locate Jay Coates, Alison Horne, or Jack Radebaugh.
The next morning, Matthew is shot in the back while jogging near his home and killed instantly. With two deaths in two days, the FBI places surviving list members under police protection and removes Jessica from the case because her own name is on the list. That same night, Arthur dies in his sleep when a stainless-steel canister hidden in his closet releases carbon monoxide through a timed valve, despite a police officer stationed outside his home.
Ethan emails Caroline after finding her university faculty page, and the two begin an intense correspondence that deepens over weeks of phone calls and video chats. They share personal stories and debate what might connect the people on the list. Caroline discovers Arthur's death through an online memorial notice. The FBI questions the recipients' parents, but no parent admits to recognizing any of the other families' names.
Jessica decides to hide rather than remain in Albany as a target. She borrows a cottage on the St. George Peninsula in Maine from a college acquaintance, leaves her iPhone behind, and drives to the coast using a paper atlas. From the cottage, she calls Art Kruse in Florida, who vaguely remembers a "Gary" who spent a summer at his parents' lake house in New Hampshire. She also calls her father, who is in an assisted living facility with worsening dementia. In a moment of lucidity, he remembers "little Artie Kruse" and says he wanted to talk about something they had done as children, but Artie refused to discuss it.
A professional hitman named Tod Fischer is hired through a chain of anonymous contacts to kill Jessica. Told only her name, her car, and that the kill must be painless, Fischer traces her location to Port Clyde, Maine, through old social media photos linking her college friend to the area. He finds her car outside the cottage, but Jessica spots him through a window. The next day, she follows Fischer's vehicle to an abandoned quarry, where a man steps out of a car with his hands raised. Jessica orders him to the ground but realizes too late that the man is bait; Fischer shoots her from a concealed position with a sniper rifle.
The FBI never locates the real Jay Coates in Los Angeles; a different man with the same name in Georgia lies and claims to have received the list, drawing police protection to himself. Alison Horne, meanwhile, deletes a voicemail from the FBI without returning the call, deliberately choosing ignorance. The real Jay Coates, consumed with rage after a friend lands a television role, goes out one night stalking a young woman through the streets. Before he can act, he is struck from behind with a steel baton and killed.
Ethan and Caroline arrange to meet in person at a cabin retreat in Makanda, Illinois. They arrive in late October and spend the evening drinking complimentary wine in their cabin. They fall asleep in each other's arms, unaware that the wine has been injected with a sedative through the cork. While unconscious, they receive lethal injections of morphine.
Sam Hamilton pursues his own investigation, drawing on his love of Agatha Christie's
And Then There Were None. He visits Frank's sister in Florida, who recalls a young girl drowning at the base of the Windward's stone jetty decades earlier. Sam searches newspaper microfilm and finds a 1956 article about the drowning of ten-year-old Faye Grant at the resort. Her family includes father John Grant, mother Lily Grant née Radebaugh, and older brother "little Jack Grant." Sam realizes that Jack Grant is Jack Radebaugh, who took his mother's maiden name.
The novel confirms that Jack Radebaugh and Jonathan Grant, Alison's benefactor, are the same person. In Bermuda, where he has invited Alison to his family's house, he tells her about his sister Faye's drowning and reveals he changed his surname to distance himself from his father. That night, he shoots Alison as she sleeps. Jack returns to Connecticut and kills his neighbor Eric, a man he considers a bully, before driving to Kennewick. At the Windward Resort, he writes a confession letter, takes sedatives, walks to the stone jetty, and crawls into the same crevice where Faye died. He drowns as the tide rises.
A month later, Sam discovers the confession hidden inside a copy of
Walt Disney's Peter Pan in the Windward's lending library. The letter explains that in the summer of 1956, a group of children at the resort formed a "Pirate Society." Inspired by the scene in
Peter Pan where Captain Hook tries to drown Tiger Lily in a rising tide, they told Faye she must survive the incoming tide in a cave at the jetty's base to earn membership. The children forgot about her and ran off to play. By the time adults noticed she was missing, Faye had drowned, and the children swore never to tell. The letter names all nine members of the Pirate Society, who are now the parents of the people on the list. Frank Hopkins, who had no children, is placed on the list directly. After being diagnosed with glioblastoma, an aggressive brain cancer, and losing his adult daughter Grace to a drunk driver, Jack spends his final years tracking down the Pirate Society members' families. He kills one child from each as retribution, viewing his acts as a restoration of order rather than revenge.
In a final section set the following March, Jessica Winslow wakes from a months-long coma. She does not remember the list or why she was shot. When her FBI colleagues Ruth Jackson and Aaron Berlin visit, she asks them to tell her what happened. Ruth prepares to recount the story, leaving Jessica as the sole surviving name on the list.