Pete Riley answers the door one morning and lets in a parent's worst nightmare. On his doorstep is Miles Lambert, a stranger who breaks the devastating news that Pete's son, Theo, isn't actually his son - he is the Lamberts', switched at birth by an understaffed hospital while their real son was sent home with Miles and his wife, Lucy. For Pete, his partner Maddie, and the little boy they've been raising for the past two years, life will never be the same again.

Abbie awakens in a daze with no memory of who she is or how she landed in this unsettling condition. The man by her side claims to be her husband. He’s a titan of the tech world, the founder of one of Silicon Valley’s most innovative start-ups. He tells Abbie that she is the perfect wife. He says she had a terrible accident five years ago and that, through a huge technological breakthrough, she has been brought back from the abyss. But as Abbie pieces together memories of her marriage, she begins to question her husband’s motives - and his version of events.

Mia and Finn are busy turning a derelict house into their dream home when Mia unexpectedly falls pregnant. But just when they think the house is ready, Mia discovers a shocking message scored into a skirting board: I WILL SAVE THEM FROM THE ATTIC. Following the clue up into the eaves, the couple make a gruesome discovery: their home was once a real-life murder house, with the evidence still concealed within the four walls.

Paul’s just here to help, or so he claims—sent by a charity for vulnerable people to do odd jobs for elderly widow Gwen. But for Gwen’s daughter Connie, there’s just something about Paul that rings alarm bells from day one. He’s a little too kind, a little too involved…Worse still, Gwen seems to have fallen under his spell.

When Eleanor Hardwicke’s beloved father dies, her world is further shattered by a gut-wrenching secret: The man she’s grieving isn’t really her dad. Eleanor was the product of an affair, and her biological father is still out there, living blissfully with the family he chose. With her personal life spiraling, a desperate Eleanor seeks him out, leading her to uncover another branch on her family tree - an infuriatingly enviable half-sister.

Foster sisters Krystal and Nichole have always been there for each other, so when Nichole is committed to a psychiatric hospital after trying to kill her husband, Krystal drops everything to defend her. Scarred by a hard upbringing, Nichole and Krystal managed to construct comfortable lives for themselves. Krystal became a respected lawyer, and Nichole was happily married to an architect - until Nichole starts raving that her husband isn’t her husband, believing that he’s an imposter.

Immi thinks she has found the perfect new home in central London: a shared warehouse with luxury accommodation, a rooftop terrace, and daily yoga, all with a surprisingly affordable price tag. The Dye Factory is a co-living community, designed to combat the loneliness of big city life. But soon after she moves into her new haven, Immi realizes that it's not quite as idyllic as it appears. No one seems to know who is behind this multi-million-pound urban experiment. And her housemates may be hiding a dangerous secret.

Christopher and Hannah are a happily married surgeon and nurse with picture-perfect lives. All that’s missing is a child. When Janie, an abandoned six-year-old, turns up at their hospital, Christopher forms an instant connection with her, and he convinces Hannah they should take her home as their own.

Emma is the one that got away. The only survivor of a serial killer known in the tabloids as “The Hairdresser”, because of the trophies he takes from his victims. The police aren't convinced. Nor is her husband. She never actually saw her tormentor properly, but now she recognizes him in every man she sees. Haunted by the horrifying incident and unwanted notoriety, Emma gives up her job as a psychiatrist and retreats from the outside world to recuperate at home, where it’s quiet. Where she can be anonymous and safe. Where no one can hurt her.

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.

Brecken Hill in upstate New York is an expensive place to live. You have to be rich to have a house there, and Fred and Sheila Merton certainly are rich. But even all their money can't protect them when a killer comes to call. The Mertons are brutally murdered after a fraught Easter dinner with their three adult kids. Who, of course, are devastated.

Sadie and Will Foust have only just moved their family from bustling Chicago to small-town Maine when their neighbor Morgan Baines is found dead in her home. The murder rocks their tiny coastal island, but no one is more shaken than Sadie. But it’s not just Morgan’s death that has Sadie on edge. And as the eyes of suspicion turn toward the new family in town, Sadie is drawn deeper into the mystery of what really happened that dark and deadly night.

When 10-year-old cousins Maddy and Brianna are arrested for a terrible crime, Maddy’s mother, Juliet, cannot believe it. How could her bright, joyful daughter be capable of such a thing? As the small village community recoils in horror, the pressure of the tragedy blows Juliet and her sister’s lives apart. And things get even worse when their daughters retreat into a self-imposed silence. Can anyone reach Maddy and discover the truth before her fate is sealed? Juliet is crushed. Nothing will ever be the same for her darling girl.

Alice and Seth are a perfect love story: the handsome doctor and his beautiful fiancée. They’re wealthy, well liked and made for each other—the envy of all their friends. Alice can’t wait for the day of their dream wedding. But when she arrives at the altar, she doesn’t recognise the man waiting to marry her. When this stranger insists he’s Seth, her husband-to-be, the entire congregation seems to agree. Even her parents try to persuade Alice to go through with the wedding.

Grace Holloway keeps to herself. Since narrowly escaping death at the hands of the man who kidnapped her, she’s thrown herself into the small inn she runs in Rock Harbor, Maine. It’s quiet, quaint and, in the off-season, completely isolated—the perfect place for Grace to keep her own secrets. But Grace isn’t the only one with something to hide, and Rock Harbor isn’t just a sleepy vacation town. Someone is taking young women—girls who look an awful lot like Grace did when she was kidnapped so many years ago.