Nina Landry awakens on her 40th birthday, anticipating a day filled with excitement. She, her new boyfriend, and her two children are taking a trip - leaving their home on Sandling Island, off the coast of England, for a dream vacation. As soon as her 15-year-old daughter, Charlie, returns from a sleepover, they can get ready to leave. But Charlie doesn’t come home at the expected time. As minutes and then hours tick by, Nina’s annoyance soon changes to concern, and then to a chilling certainty that something terrible has happened.

When Hannah and her boyfriend, Simon, set out to Amsterdam, they’re confident that they’ll make it to his sister’s wedding in time. However, unbeknownst to them, their train is scheduled to divide in the middle of the night. And when it does, half of it continues the route to Amsterdam. And the other half—the one with Hannah in it—heads three hundred miles away, to Paris. Left without her belongings or hope of reuniting with Simon, Hannah has no choice but to spend the day in Paris before the next train out.

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.

On a beautiful summer night in a charming English suburb, a young woman and her boyfriend disappear after partying at the massive country estate of a new college friend. One year later, a writer moves into a cottage on the edge of the woods that border the same estate. Known locally as the Dark Place, the dense forest is the writer’s favorite place for long walks and it’s on one such walk that she stumbles upon a mysterious note that simply reads, “DIG HERE.”

Gifted musician Clemency Thompson is playing for tourists on the streets of Southern France when she receives an urgent text message. Her childhood friend, Lucy, is demanding her immediate return to London. It’s happening, says the message. The baby is back. Libby Jones was only six months old when she became an orphan. Now 25, she’s astounded to learn of an inheritance that will change her life. A gorgeous, dilapidated townhouse in one of London’s poshest neighborhoods has been held in a trust for her all these years. Now, it’s hers.

Seventeen-year-old Lenni Pettersson lives on the Terminal Ward at the Glasgow Princess Royal Hospital. Though the teenager has been told she’s dying, she still has plenty of living to do. Joining the hospital’s arts and crafts class, she meets the magnificent Margot, an 83-year-old, purple-pajama-wearing, fruitcake-eating rebel, who transforms Lenni in ways she never imagined. As their friendship blooms, a world of stories opens for these unlikely companions who, between them, have been alive for one hundred years.

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.

Shuggie’s mother Agnes walks a wayward path: She is Shuggie’s guiding light but a burden for him and his siblings. She dreams of a house with its own front door while she flicks through the pages of the Freemans catalogue, ordering a little happiness on credit, anything to brighten up her grey life. Married to a philandering taxi-driver husband, Agnes keeps her pride by looking good - her beehive, make-up, and pearly-white false teeth offer a glamourous image of a Glaswegian Elizabeth Taylor.

When she was 9 years old, Melody Browne's house burned down, and it took all of her childhood memories with it. Now she's a single mother of a teenage boy living in Central London. She hasn't seen her parents since she left home at 15, but she doesn't mind. She's better off on her own. She works as a dinner lady at her son's school and has no idea where her humdrum life is heading. But one summer's night, a hypnotist inadvertently unlocks memories of her childhood, and her whole life is turned upside down.

Alice, a novelist, meets Felix, who works in a warehouse, and asks him if he’d like to travel to Rome with her. In Dublin, her best friend, Eileen, is getting over a break-up, and slips back into flirting with Simon, a man she has known since childhood. Alice, Felix, Eileen, and Simon are still young—but life is catching up with them. They desire each other, they delude each other, they get together, they break apart.

Emily Proudman just lost her acting agent, her job, and her apartment in one miserable day. Scott Denny, a successful and charismatic CEO, has a problem that neither his business acumen nor vast wealth can fix. Until he meets Emily. Scott offers Emily a summer job as a housekeeper on his remote, beautiful French estate. Enchanted by his lovely wife Nina, and his eccentric young daughter, Aurelia, Emily falls headlong into this oasis of wine-soaked days by the pool. But soon Emily realizes that Scott and Nina are hiding dangerous secrets.

Edie is stumbling her way through her 20s - sharing a subpar apartment in Bushwick, clocking in and out of her admin job, making a series of inappropriate sexual choices. She is also haltingly, fitfully giving heat and air to the art that simmers inside her. And then she meets Eric, a digital archivist with a family in New Jersey, including an autopsist wife who has agreed to an open marriage - with rules.

Lex Gracie doesn't want to think about her family. She doesn't want to think about growing up in her parents' House of Horrors. And she doesn't want to think about her identity as Girl A: the girl who escaped, the eldest sister who freed her older brother and four younger siblings. It's been easy enough to avoid her parents - her father never made it out of the House of Horrors he created, and her mother spent the rest of her life behind bars. But when her mother dies in prison and leaves Lex and her siblings the family home, she can't run from her past any longer.

A recurrent, unidentifiable noise in her apartment. A memo to her boss that's replaced by obscene insults. Amanda - a successful architect in a happy marriage - finds her life going off kilter by degrees. She starts smoking again, and one night for no reason, without even the knowledge that she's doing it, she burns her husband with a cigarette. At night she dreams of a beautiful woman with pointed teeth on the shore of a blood-red sea.

In the 1950s, ex-boxer Norman Alonso is a determined and humble Jamaican who has immigrated to Britain with his wife and children to secure a brighter future. Blighted with unexpected illness and racism, Norman and his family are resilient, but are all too aware that their family will need more than just hope to survive in their new country.