Susan is a freelance editor in her fifties who recently left her life in Crete to return to London. She takes on assignments out of financial necessity, including the continuation of the Atticus Pund mystery series. Her past experiences with demanding authors make her cautious about the new manuscript and the secretive family behind it.

Eliot is a 32-year-old author writing the new Atticus Pund novel. As the grandson of the famous children's author Miriam Crace, he grew up at the luxurious Marble Hall. He struggles with substance use and harbors deep resentment toward his family, using his new manuscript to air his grievances and encode real-life secrets.

Atticus is the famous fictional detective from the 1950s mystery series. He is a German-born investigator from a Greek Jewish family who survived a prison camp during World War II. Slowly dying from an illness, he agrees to travel to the South of France to investigate a client's fears.

Miriam is the deceased matriarch of the Crace family and a wildly successful children's author. While the public views her as a benevolent creator, her family privately remembers her as a controlling and cruel woman who used non-disclosure agreements to silence her relatives and protect her brand.

Lady Margaret is the wealthy owner of Chateau Belmar in the fictional narrative. Suffering from terminal mitral stenosis, she writes a letter begging Atticus to investigate disturbing information she recently overheard. Her sudden death initiates the core mystery of the embedded novel.

Charles is the former CEO of Cloverleaf Books, currently imprisoned for killing author Alan Conway and attempting to kill Susan. Prison conditions have changed him significantly from the cultured publisher he once was, replacing his polite demeanor with anger and bitterness.

Elaine is the wife of imprisoned publisher Charles Clover. She maintains an immaculate outward appearance despite the collapse of her husband's career. She approaches Susan to rekindle their old friendship and asks her to watch over Eliot.

James is the loyal, 30-year-old assistant to detective Atticus Pund in the embedded narrative. He manages the logistics of their investigations, takes diligent notes during interviews, and frequently struggles with translating French during their trip to Chateau Belmar.

Gillian is Eliot's wife and a professional nurse. She met Eliot when he was hospitalized for an overdose. Her marriage is strained by Eliot's erratic behavior and addictions, leaving her visibly anxious during social interactions.

Alice is the secretary to lawyer Jean Lambert in the embedded fictional narrative. She assists with his legal practice and displays highly nervous behavior when the Chalfont family arrives in town.

Frederick is the manager of the Marble Hall museum and the adopted son of Miriam Crace. He moves with difficulty and wears an eyepatch due to a severe car accident. He vigorously defends Miriam's reputation against Eliot's negative claims and maintains tight control over the estate's physical grounds.

Frederic is a police officer with the French Surete in the embedded narrative. He sustained physical disabilities from a hand grenade during World War II, which initially causes him to harbor hostility toward the German-born Atticus before learning of the detective's own wartime suffering.

Edward is Eliot's father and Miriam's son. He runs a private art foundation and sports a white beard. He harbors intense guilt over his inability to protect his children from Miriam's toxic influence, having chosen the financial security of the estate over family harmony.

Elmer is Margaret's American second husband in the fictional narrative. He operates the Galerie Werner-Waysmith and prioritizes his art business above family matters. His status as an outsider and his impending financial inheritance make him a prime suspect in Margaret's death.

Roland is Eliot's brother. He works for the Crace estate alongside his uncle Jonathan, helping to negotiate television and film deals for Miriam's intellectual property. He maintains a polite public face regarding Miriam while privately acknowledging her cruelty to Susan.

Robert is Elmer's 32-year-old son in the fictional narrative. He manages his father's art galleries but holds deep resentment toward Elmer for forbidding his painting career and for the tragic death of his biological mother.

Julia is Eliot and Roland's sister. She changed her last name to distance herself from the Crace family after enduring years of cruel insults from Miriam regarding her weight. She relies on therapy and distance to maintain her peace.

Judith is Margaret's daughter in the embedded mystery novel. Working as an ethnographer researching the Nazca Lines in Peru, she hopes to secure financial support from her mother's estate to fight government interference in her work.

Jonathan is Miriam's son and the head of the Crace Estate. He fiercely protects the family's public image and the lucrative children's book brand, threatening legal action against anyone who might cause a scandal. He firmly denies any negative accounts of his mother's behavior.

Jeffrey is Margaret's son and the 7th Earl of Chalfont in the fictional narrative. He struggles with significant gambling debts and relies on small stipends from his wealthy mother to stay afloat.

Leylah is Jonathan's Egyptian wife. She carries immense grief over the tragic death of her daughter Jasmine and relies heavily on alcohol to cope with her restrictive life inside the Crace family.

Lola is Jeffrey's wife in the fictional narrative. A retired actress, she hopes Margaret will finance a stage production to facilitate her return to the spotlight.

Dr. Lambert is Miriam Crace's former physician. Now in his seventies and driving a luxury Jaguar, he signed a non-disclosure agreement regarding Miriam's health and insists she died of natural causes.

Jean is Margaret's lawyer in the fictional narrative. He dresses in old-fashioned suits and handles the administration of Margaret's complex will and estate.

Beatrice is the housekeeper and cook at Chateau Belmar in the embedded mystery. She maintains the household routines and specifically avoids looking at a Cezanne painting in the house due to her wartime memories.

Harlan is an art historian in the fictional narrative who investigates and recovers art stolen from Jewish families by the Nazis during World War II. He monitors Elmer's gallery closely for illicit pieces.

Michael is the head of Causton Books and Susan's boss. He commissions Eliot's novel primarily as a strategic move to secure publishing rights for the lucrative children's brand from the Crace estate, placing commercial interests above editorial quality.

Ian is a Detective Inspector with the police. A widower with an avid interest in mystery novels, he views Susan more as an asset to understanding Eliot's literary clues than as a suspect.

Emma is a Detective Constable working alongside Blakeney. She is highly suspicious of Susan's presence at the crime scene and aggressively pushes for her arrest, acting as a foil to Blakeney's more collaborative approach.

Harry is Judith's husband in the fictional narrative. He is attempting to build a hotel and frequently asks for financial assistance. His name is a reference to a character in Miriam's children's books.

Cedric is Lola's young son in the embedded mystery novel. Precocious and theatrical, he has an unsettling fascination with the poisonous plants in the chateau's garden. He serves as the literary counterpart to a young Eliot Crace.