The Postscript Murders (harbinder Kaur, #2)

In the seaside town of Shoreham-by-Sea, on the south coast of England, ninety-year-old Peggy Smith sits by the bay window of her sheltered housing flat at Seaview Court, meticulously recording the movements of two suspicious men in a white Ford Fiesta who appear to be watching her building. When Natalka Kolisnyk, a twenty-seven-year-old Ukrainian carer, arrives for Peggy's evening call, she finds the old woman dead in her armchair. The death of a ninety-year-old raises no immediate alarms, but Natalka discovers a business card beside Peggy that reads "Mrs M. Smith. Murder Consultant."

Natalka brings her suspicions to DS Harbinder Kaur, a thirty-six-year-old Sikh detective at the local police station who is gay but closeted and lives above her parents' shop with her mother Bibi and father Deepak. Natalka explains that Peggy's crime novels are all dedicated to her or mention her in the acknowledgements, including books by the bestselling author Dex Challoner. Harbinder is intrigued but sees nothing overtly suspicious.

Natalka enlists two of Peggy's other friends: Benedict Cole, a thirty-two-year-old former monk who runs a beachfront coffee shack, and Edwin Fitzgerald, Peggy's eighty-year-old neighbor and retired BBC producer. After Peggy's funeral, Edwin reveals he found a postcard inside Dex's latest novel reading "We are coming for you." When Natalka and Benedict break into Peggy's flat to search for clues, a masked gunman bursts in, grabs a novel called Thank Heaven Fasting by golden-age crime writer Sheila Atkins, and flees. Benedict notices that a holy picture of St. Patrick fell from the stolen book.

Harbinder visits Dex at his expensive seafront home. Dex explains that Peggy was friends with his late mother, Weronika, a Polish woman who had been a teenage assassin in the wartime resistance. Peggy and Weronika discussed murders together, and Peggy's expertise became invaluable to Dex's writing. At a book event in Chichester, Dex confides that his mother had been frightened before her death, believing someone was spying on her, and wonders whether both Weronika and Peggy were murdered. The next morning, Dex is found shot dead in his home.

The investigation expands quickly. Harbinder and her partner DS Neil Winston interview key figures in Dex's life, including his editor Miles Taylor at the publishing house Seventh Seal, his publicist Pippa Sinclair-Lewis, and his agent Jelli Walker-Thompson. Jelli reveals that Dex had been secretly planning a novel called The Murder Consultant, about an elderly woman who solves crimes, based on Peggy. Harbinder contacts J. D. Monroe, another author who credited Peggy, and learns that Julie Monroe, as J. D. Monroe is known, also received a "We are coming for you" postcard. Julie is heading to a crime-writing festival in Aberdeen.

Natalka confides to Harbinder that she has her own reasons for fear. She co-founded a cryptocurrency business in Ukraine and took a portion of the funds when she left the country; the dangerous investors pursuing her are the men in the white Ford Fiesta. She also relays what her colleague Maria, a Polish carer, told her: Peggy once said Weronika's death was suspicious and that the clue was hidden in Thank Heaven Fasting.

Natalka, Benedict, and Edwin drive to Aberdeen for the festival, where they encounter Lance Foster, a literary author whose novel Laocoön acknowledged Peggy. At Julie's panel, Lance asks from the audience, "Who do you think killed Peggy Smith?" He reveals he too received one of the postcards. In a pub that evening, Natalka overhears two men speaking Ukrainian and flees in a panic with Benedict. Edwin spots Peggy's son Nigel Smith in the Travelodge lobby, surprised he is in Aberdeen at all. Harbinder later discovers no room was booked under Nigel's name. The next day, Benedict sees Nigel leaving the hotel with Lance and learns the two attended the same private school.

When Lance fails to appear for a planned meeting, the trio finds him dead in his hotel room. A pathologist discovers syringe marks and abnormally low blood glucose, indicating death by insulin poisoning, a method entirely different from the gunshot that killed Dex. DI Jim Harris of the Aberdeen police requests Harbinder's assistance.

Jim moves the group to a safe house on the coast. Miles privately tells Harbinder he received an anonymous manuscript called Amanuensis that mirrors Dex's secret project. While Edwin and Julie are at a hospital after Julie breaks her wrist on the beach, a Ukrainian gunman named Andriy enters the house and points a weapon at Miles, accusing him of betrayal. Benedict throws himself in front of Natalka when the gun swings toward her; the bullet hits the wall. A second man enters: Dmytro, Natalka's brother, whom she believed was dead after he went missing during the war in Ukraine. Harbinder disarms Andriy and learns that Miles, during a university year abroad in Russia, met Ukrainian contacts of Peggy and her friend Joan in Moscow and inadvertently betrayed Andriy to Russian authorities, leading to his imprisonment. Andriy, now a refugee in Aberdeen, recognized Miles at the festival. Dmytro, released in a prisoner exchange, recognized Natalka in a photograph Andriy took at the pub.

Back in Shoreham, Neil obtains CCTV footage that initially shows Maria outside Dex's house on the night of his murder but then reveals Patricia Creeve, the manager of Care4You, the care agency where Natalka works, outside the house with a gun. Harbinder races home, knowing Patricia is currently caring for her mother, who recently broke her leg, and finds Bibi safe; the family dog, Starsky, has cornered Patricia in the kitchen. Patricia is arrested. Harbinder reconstructs the case: Patricia had a gambling addiction and had been stealing from elderly clients, including Weronika. When Weronika grew suspicious, Patricia killed her. Peggy suspected Patricia and left a coded clue, the holy picture of St. Patrick (Patrick/Patricia) tucked inside Thank Heaven Fasting. Maria had shared Peggy's suspicions with Dex, who called Patricia; Patricia came to his house and shot him. Maria, fearing for her life, fled with her family but is later found safe. Nigel's wife Sally reveals that Nigel wrote Amanuensis himself, having learned of Dex's secret project through Peggy, and submitted it anonymously to Miles.

Benedict then uncovers a second killer. Reading Peggy's Investigation Book, he notices that on the day Peggy died, a woman with a Jack Russell was seen from Peggy's window, matching Julie's dog, despite Julie's claim she never met Peggy. He also realizes Julie's debut novel plagiarized the plot of Thank Heaven Fasting. He and Natalka race to Brighton to warn Harbinder, who is walking the seafront with Julie. Harbinder has already deduced Julie's guilt: The masked gunman who stole the Atkins book held the weapon in the left hand, and Julie is left-handed, while Patricia is right-handed. Julie killed Peggy by insulin injection to protect her secret and killed Lance because he recognized the plagiarism, a method consistent with her former career as a nurse. Julie confesses, and a forensic psychologist concludes she may also have killed her own mother. Harbinder is shaken, having developed romantic feelings for Julie.

The threatening postcards turn out to be harmless: Pippa explains they were a marketing stunt by a young publicist promoting an unrelated debut novel.

In the aftermath, Natalka and Benedict begin a relationship, and Natalka takes over Care4You with Maria's help. Benedict discovers that Sheila Atkins was Lance's mother, explaining Lance's deep connection to Peggy, and theorizes that "the bay window set," a phrase from Lance's dedication, referred to elderly friends, including Peggy, Weronika, and Sheila, who gathered by the bay windows at Seaview Court. Harbinder's father tells her he knows she is gay and that both parents accept her. Sally invites the trio to a farewell tea party in Peggy's empty flat, where they toast her memory with champagne as the sun streams through the bay window.