The Chateau

Four college friends, now turning 40, reunite at a chateau in Saint-Rémy-de-Provence at the invitation of Séraphine Demargelasse, the elderly matriarch of the estate. Séraphine summons her granddaughter Darcy and Darcy's three closest friends: Jade, who carries a secret connection to the chateau's past; Vix, a painter recovering from a preventative mastectomy after a breast cancer diagnosis; and Arabelle, a celebrity chef who grew up on the property as the granddaughter of Sylvie, Séraphine's longtime housekeeper. The novel opens with a flash-forward: Jade wakes to screams and discovers Séraphine dead in bed, a knife in her chest. The narrative then rewinds two days to trace the events leading to the murder and its aftermath.

Darcy arrives in Provence with her husband Oliver and their two young children, Mila and Chase. She and Oliver are drowning in debt, and her start-up, The Fertility Warrior, a subscription service for women struggling with infertility, is failing. Séraphine's invitation includes a note about discussing her Last Will and Testament, which both intrigues and unnerves Darcy. She is also harboring a private fury: A week earlier, she overheard Oliver confessing to a neighbor that he is in love with one of her best friends. Because Vix is a lesbian, Darcy assumes the other woman is Jade. In retaliation, Darcy created an anonymous Instagram account, @imwatchingyou88, to post threatening messages aimed at Jade.

Séraphine, privately battling terminal blood cancer she has disclosed to no one, has summoned the women for a larger purpose. She arranges a secret meeting with Vix and announces at dinner that after Jade's birthday, she will share revelations that will be painful for some of them. Meanwhile, the @imwatchingyou88 posts unsettle the group, though no one identifies Darcy as the account's creator.

The morning after Jade's 40th birthday party, Vix arrives at Séraphine's room for their scheduled 6:00 a.m. meeting and finds her murdered. A bedside clock lies smashed on the floor, its face frozen at 3:16, and the bedroom safe hangs open. Police arrive, led by Officer Darmanin, and declare everyone a suspect. Arabelle reveals that Séraphine and Sylvie were secret romantic partners for decades and confesses she has an alibi: Oliver was with her at the time of the murder. They have been having an affair. Darcy is devastated but controlled, realizing she suspected the wrong friend.

A torn piece of notepaper in Séraphine's bedsheets reads "Assassiné R," meaning "Murdered R." The group assumes the R refers to Raph, the young groundskeeper whose lack of agricultural knowledge has already raised suspicion, and the police take him into custody.

The estate attorney reads Séraphine's Will. Darcy inherits the bulk of the fortune, including the chateau and investments. Sylvie and Vix each receive five million euros in trust, stunning Darcy, who had no idea Séraphine had been paying Vix five thousand euros monthly for 20 years. Raph is left five hundred thousand euros. Séraphine also left a sealed letter for Sylvie.

Before Sylvie can read the letter, someone knocks her unconscious with a copper pot and steals it. Because Raph is still in police custody, he could not have committed this assault, and the police release him. Raph later confides in Darcy that he is not really a groundskeeper but a trained security professional seeking Séraphine's financial help for a custody battle over his children. Darcy confesses she created the Instagram account. Raph follows it, becoming her only follower, a detail that later proves critical.

At Van Gogh's former sanatorium nearby, Jade tells Vix the full story of her family. During World War II, Jade's Jewish grandparents surrendered their two most precious possessions to the Demargelasse family in exchange for being hidden at the chateau: a diamond necklace and a painting by Vincent van Gogh, an improved version of his famous Starry Night, gifted by the artist to Jade's great-great-grandmother. After two months, the mother of Darcy's grandfather Rainier ordered the family expelled, sending Jade's grandparents to their deaths at Auschwitz. Séraphine saved Jade's father Maurice, then 10 years old, by taking him to an orphanage. Vix reveals that during their study-abroad semester, Séraphine asked her to paint over the Van Gogh so it could be concealed but later restored, a favor that initiated the decades of financial support. At Darcy's wedding years later, Jade and Darcy stole the diamond necklace from Séraphine's safe; the single diamond Jade wears is all that remains.

Darcy discovers that a hidden room under the chateau's stairs, which Arabelle claimed was sealed during renovations, is still accessible. Inside, she finds the Van Gogh, a letter from Séraphine addressed to Jade, and a basket containing bloodstained clothes and surgical gloves. She also finds the torn top half of the note from Séraphine's bed. The full message reads not "Murdered Raph" but "Arabelle Murdered Rainier," revealing that as a child, Arabelle deliberately shoved Rainier into a pool statue, killing him.

Séraphine's letter discloses a staggering secret: When the family was expelled, Séraphine kept baby Arnaud, Jade's father's infant brother, and raised him as her own son under the name Antoine. Antoine became Darcy's father. Darcy and Jade are therefore first cousins, and Darcy is ethnically Jewish through her father.

Before Darcy can process this, Arabelle appears holding a gun and admits to murdering Séraphine and assaulting Sylvie. Her motive stretches back to childhood. As a girl, she overheard Sylvie confide to Séraphine that Rainier had raped Sylvie. Sylvie's daughter Delphine was Arabelle's mother, making Rainier Arabelle's biological grandfather. Arabelle resented that Rainier doted on Darcy while ignoring his biological granddaughter, and as a child she deliberately killed him. When the terminally ill Séraphine tells Arabelle she intends to expose the truth, Arabelle murders her. Now Arabelle plans to kill Darcy and frame her as Séraphine's murderer, using planted fingerprints and Darcy's @imwatchingyou88 posts as evidence. She forces Darcy to post a final threatening message tagging @underthestairs. Sylvie, who has found a duplicate of Séraphine's letter hidden beneath the chateau's ancient plane tree, stumbles upon the confrontation and is forced into the room at gunpoint.

Raph, searching the chateau after hearing Darcy's screams, spots the cryptic post and decodes the @underthestairs tag. He finds the hidden panel, enters with his gun, and confronts Arabelle from behind. She fires at Darcy, but Raph dives to shield her while shooting Arabelle simultaneously. Both are wounded; Darcy and Sylvie survive.

Two weeks later, the survivors begin rebuilding. Vix reconnects with her ex-girlfriend Juliet, gives away her inheritance, and begins painting with renewed purpose. Jade eats an ice cream treat she has denied herself for nearly 30 years, a symbolic release from food restriction rooted in her father's trauma, and resolves to pursue humanitarian work. Darcy tells Oliver she forgives him but will not fight for the marriage, then recovers in Nice with Sylvie and the children.

In a final chapter, Oliver visits Arabelle in prison. She reveals he is her accomplice: He helps plan the murder, holds the gun while she searches the safe, and watches her kill Séraphine without intervening. She manipulates him by claiming Séraphine abused her and that the death would unlock Darcy's inheritance to settle their debts. Arabelle discloses that she recorded their planning conversation and uploaded it to a secure server. She delivers an ultimatum: Unless Oliver kills Darcy, she will expose him. Though the murder mystery is solved and Darcy has survived, the novel closes on this open, unresolved threat, with Arabelle asking which parent his children will lose.