Early one morning on the shore of the Thames, DCI Samuel Owusu is called to the scene of a gruesome discovery. When Owusu sends the evidence for examination, he learns the bones are connected to a cold case that left three people dead on the kitchen floor in a Chelsea mansion thirty years ago. Rachel Rimmer has also received a shock—her husband, Michael, has been found dead in the cellar of his house in France. All signs point to an intruder, and the French police need her to come urgently to answer questions about Michael and his past that she very much doesn’t want to answer.

Celebrating her forty-fifth birthday at her local pub, popular podcaster Alix Summer crosses paths with an unassuming woman called Josie Fair. Josie, it turns out, is also celebrating her forty-fifth birthday. They are, in fact, birthday twins. A few days later, Alix and Josie bump into each other again, this time outside Alix’s children’s school. Josie has been listening to Alix’s podcasts and thinks she might be an interesting subject for her series. She is, she tells Alix, on the cusp of great changes in her life.

Welcome to North Falls—a small town where everyone knows everyone. Or so they think. Until the night of the fireworks. When two teenage girls vanish, and the town ignites. For Officer Emmy Clifton, it’s personal. She turned away when her best friend's daughter needed help—and now she must bring her home. But as Emmy combs through the puzzle the girls left behind, she realizes she never really knew them. Nobody did. Every teenage girl has secrets. But who would kill for them? And what else is the town hiding?

Owen Pick’s life is falling apart. In his 30s and living in his aunt’s spare bedroom, he has just been suspended from his job as a teacher after accusations of sexual misconduct - accusations he strongly denies. Searching for professional advice online, he is inadvertently sucked into the dark world of incel forums, where he meets a charismatic and mysterious figure. Across the street from Owen lives the Fours family, headed by mom Cate, a physiotherapist, and dad Roan, a child psychologist. But the Fours family have a bad feeling about their neighbor Owen.

Restauranteur Paddy Swann was the life of the party until the day a man pushed him in the path of an oncoming train, leaving his twenty-something daughter Ash and wife Nina devastated. Shortly after Paddy’s funeral, the two women receive a surprise in the mail: a note and package from Nick Radcliffe, an old friend of Paddy’s, and a nondescript lighter that once belonged to him decades ago. This unexpected gift draws Nick and Nina closer together—much to Ash’s dismay.

Melville Heights is one of the nicest neighborhoods in Bristol, England. It’s the sort of place where doctors and lawyers and old-money academics live. It’s not the sort of place where people get stabbed in the back 30 times with a kitchen knife in their own homes. Someone must have seen something. Newlywed Joey Mullen, for example, recently returned from four years of working in Ibiza. She and her husband, Alfie, are eager to find a place of their own in her hometown. But Joey finds herself distracted by the man next door, Tom Fitzwilliam.

Nisha Cantor lives the globetrotting life of the seriously wealthy, until her husband announces a divorce and cuts her off. Nisha is determined to hang onto her glamorous life. But in the meantime, she must scramble to cope--she doesn’t even have the shoes she was, until a moment ago, standing in. That’s because Sam Kemp—in the bleakest point of her life—has accidentally taken Nisha’s gym bag. But Sam hardly has time to worry about a lost gym bag—she’s struggling to keep herself and her family afloat.

In a windswept British seaside town, single mum Alice Lake finds a man sitting on the beach outside her house. He has no name and no idea how he got there. Against her better judgment, she invites him inside. Meanwhile, in a suburb of London, 21-year-old Lily Monrose has been married for only three weeks. When her husband fails to come home from work one night, she is left alone in a place where she knows no one and with the police telling her that her husband never existed.

Sydney Shaw, like every single woman in New York, has terrible luck with dating. She's seen it all: men who lie in their dating profile, men who stick her with the dinner bill, and worst of all, men who can't shut up about their mothers. But finally, she hits the jackpot. Her new boyfriend is utterly perfect. He's charming, handsome, and works as a doctor at a local hospital. Sydney is swept off her feet.

There are three rules Brooke Sullivan must follow as a new nurse practitioner at a men’s maximum-security prison: 1) Treat all prisoners with respect. 2) Never reveal any personal information. 3) Never EVER become too friendly with the inmates. But none of the staff at the prison knows Brooke has already broken the rules. Nobody knows about her intimate connection to Shane Nelson, one of the penitentiary’s most notorious and dangerous inmates.