When Cassie Fitzgerald was at school in the late ’90s, she and her friends killed a fellow student. Almost 20 years later, Cassie is a happily married mother who loves her job --- as a police officer. She closely guards the secret she has all but erased from her memory. One day, her husband finally persuades her to go to a school reunion. But then, shockingly, one of her old friends, Garfield Rice, is found dead in the school bathroom, supposedly from a drug overdose. Garfield was an eminent --- and controversial --- MP, and the investigation is high profile. The trouble is, Cassie can’t shake the feeling that one of them has killed again. Is Cassie right, or was Garfield murdered by one of his political cronies?

Three years after her mother’s death, Ruth Galloway is finally sorting through her things when she finds a curious relic: a decades-old photograph of her own Norfolk cottage --- before she lived there --- with a peculiar inscription on the back. Ruth returns to the cot­tage to uncover its meaning as Norfolk’s first cases of COVID-19 make headlines, leaving her and Kate to shelter in place there and befriend a kind neighbor, Zoe. Meanwhile, Nelson is investigating a series of deaths of women that may or may not be suicide. When he links a case to an archaeological dis­covery, he breaks curfew to visit Ruth and enlist her help. But the further Nelson investigates the deaths, the closer he gets to Ruth’s isolated cottage --- until Ruth, Zoe and Kate all go missing, and Nelson is left scrambling to find them before it’s too late.

Ruth Galloway is back as head of archaeology at the University of North Norfolk when a group of local metal detectorists --- the so-called Night Hawks --- uncovers Bronze Age artifacts on the beach, alongside a recently deceased body, just washed ashore. Not long after, the same detectorists uncover a murder-suicide --- a scientist and his wife found at their farmhouse, long thought to be haunted by the Black Shuck, a humongous black dog, a harbinger of death. The further DCI Nelson probes into both cases, the more intertwined they become, and the closer they circle to David Brown, the new lecturer Ruth has recently hired, who always seems to turn up wherever Ruth goes.

The death of a 90-year-old woman with a heart condition should not be suspicious. Detective Sergeant Harbinder Kaur certainly sees nothing out of the ordinary when Peggy’s caretaker, Natalka, begins to recount Peggy Smith’s passing. But Natalka had a reason to be at the police station. While clearing out Peggy’s flat, she noticed an unusual number of crime novels, all dedicated to Peggy. And each psychological thriller included a mysterious postscript: PS: for PS. When a gunman breaks into the flat to steal a book and its author is found dead shortly thereafter, Detective Kaur begins to think that perhaps there is no such thing as an unsuspicious death after all.

Ruth Galloway has a new job, home and partner, and she is no longer North Norfolk police’s resident forensic archaeologist. That is, until convicted murderer Ivor March offers to make DCI Nelson a deal. Nelson was always sure that March killed more women than he was charged with. Now March confirms this and offers to show Nelson where the other bodies are buried --- but only if Ruth will do the digging. March tells Ruth that he killed four more women and that their bodies are buried near a village bordering the fens, said to be haunted by the Lantern Men, mysterious figures holding lights that lure travelers to their deaths. Is Ivor March himself a lantern man, luring Ruth back to Norfolk? What is his plan, and why is she so crucial to it? And are the killings really over?

Clare Cassidy is no stranger to murder. A high school English teacher specializing in the Gothic writer R. M. Holland, she teaches a course on it every year. But when one of Clare’s colleagues and closest friends is found dead, with a line from Holland’s most famous story, “The Stranger,” left by her body, Clare is horrified to see her life collide with the storylines of her favorite literature. To make matters worse, the police suspect the killer is someone Clare knows. Unsure whom to trust, she turns to her closest confidant: her diary. Then one day she notices writing that isn't hers, left on the page of an old diary: Hallo Clare. You don’t know me. “The Stranger” has come to terrifying life. But can the ending be rewritten in time?