Maggie and Brad are on vacation at Lake Tahoe when they meet another couple, Skye and Joe. The four hit it off so well that Maggie invites their new friends to share her beautiful lakeside rental. What she doesn’t realize is Skye and Joe aren’t just some random couple. They have been watching Maggie and Brad and have chosen them carefully.

Victoria Barnett has it all: a great career as a nurse practitioner, a handsome and loving husband, a beautiful home in the suburbs, and a plan to fill it with children. Life is perfect—or so it seems. Then she’s in a terrible accident...and everything falls apart. Now Victoria is unable to walk. She can’t feed or dress herself. She can’t even speak. She is confined to the top floor of her house with 24-hour care.

The white-washed Italian villa is perfect. I thought it might feel odd, living in a stranger’s house for the summer, but as my husband and children swim in the infinity pool, I start to relax. And then, in the back of a wardrobe, I find something that shatters everything.... Sparkling green eyes, square jaw, lopsided smile. A young man with his arm around a beautiful woman. The picture is old and faded, but I’d recognize him anywhere. The man is my husband.

When Kate Burke is awakened one night by a sound outside her window, her PTSD is triggered. Was it simply a deer crossing her secluded backyard? Or was it intruders? Because Kate still lives with the dreadful memories of her husband’s murder during a seemingly random home invasion two years before, she knows the answer can mean the difference between life and death. But when she discovers the unsettling ways her property has been vandalized the next day, Kate is forced to conclude the worst: someone is watching her.

My husband was not a monster. No matter what they say.... The day my husband, Michael, stepped in front of a lorry after being questioned by the police, my world fell apart. He was devoted to me and our six-year-old daughter. But they’d connected him to the disappearance of a young mother from our tiny village.

Behind closed doors I try to relax, to unwind in the huge clawfoot bath and forget about my complicated past. It’s hard being the new couple on the street when you’ve got secrets. Because the truth is, my charming husband isn’t really my husband. And I’m not Stephanie Hamlin....

When Maggie sees the beautiful Venetian blinds moving in the Caldwells' front window, she freezes. Her favorite neighbors Cady and Josh are away, so who is in their house? The pretty young woman who answers the door tells a convincing story. She's Sarah. The house-sitter. Just here for a month. An old friend of Cady's who needed a place to stay. She's pleasant and warm, and Maggie wanders back to her house thinking she might have made a new friend. Yet she can't help but wonder why Cady never mentioned Sarah.

Newlywed Jade Westmore has finally found her forever in husband Wells, a charming, successful, and recently divorced architect—only there’s one caveat: behind the gates of their elysian estate, hidden from street view in the caretaker’s cottage … lives Wells’s first wife, Sylvie. Three years ago, the original Mrs. Westmore suffered a nervous breakdown—and hasn’t uttered a sound since. Not a physician, psychologist, or world-renown specialist has been able to elicit so much as a word from the silent woman … until now.

Amy Whey is proud of her ordinary life and the simple pleasures that come with it - teaching diving lessons, baking cookies for new neighbors, helping her best friend, Charlotte, run their local book club. But Amy’s sweet, uncomplicated life begins to unravel when the mysterious and alluring Angelica Roux arrives on her doorstep one book-club night. Something wicked has come her way - a she-devil in a pricey red sports car who seems to know the terrible truth about who she is and what she once did.

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.

Breezing into the tony seaside paradise of Westport, Connecticut, gorgeous thirtysomething Piper Reynard sets down roots, opening a rehab and wellness space and joining a local yacht club. When she meets Leo Drakos, a handsome, successful lawyer, the wedding ring on his finger is the only thing she doesn’t like about him. Yet as Piper well knows, no marriage is permanent.

Ainsley Greenburg is a fixer. It’s what she prides herself on. So when Ainsley realizes her marriage is at its breaking point, she makes a decision to repair it, no matter the cost. Approaching her husband to propose the arrangement is supposed to be the hard part, but Peter agrees to the salacious plan almost immediately. The rules are simple: They will each date someone new once a week. They will never discuss what happens on the dates. Soon, though, the rules are broken, turning terrible mistakes into unspeakable consequences.

Lieutenant Abby Mullen is no stranger to crisis. As the hostage negotiation instructor for the NYPD, she deals with worst-case scenarios every day. Nothing fazes her anymore. That all changes when she gets a call from Eden Fletcher, a fellow survivor of the infamous Wilcox cult. The two haven’t spoken since the night of a tragic, fiery massacre, when their paths diverged. But now Eden needs Abby’s help: someone has kidnapped her son and is demanding a $5 million ransom. As Abby throws herself into the case, she can’t help but wonder why the kidnapper has targeted Eden.

Selena Murphy is commuting home on the train when she strikes up a conversation with a beautiful stranger in the next seat. The woman introduces herself as Martha and soon confesses that she’s been stuck in an affair with her boss. Selena, in turn, confesses that she suspects her husband is sleeping with the nanny. When the train arrives at Selena’s station, the two women part ways, presumably never to meet again.

Gemma Robinson comes into Elliot’s life like a whirlwind, and they marry and settle into his home. When she asks him if her parents can come to stay for a couple of weeks, he is keen to oblige - he just doesn’t quite know what he’s signing up for. The Robinsons arrive with Gemma’s sister, Chloe, a mysterious young woman who refuses to speak or leave her room.

Tara Logan adores her perfect little family: husband, Noah, and two children, teenager Rosie and 11-year-old Spencer. But her happiness is shattered when she wakes in her neighbour Lee Jacobs' bed, with no memory of how she got there or what happened between them. And worse - he has been stabbed to death. Convinced she didn't kill Lee, Tara flees home and stays silent, holding her breath as the investigation grips the neighbourhood.

When 14-year-old Brittany disappears one night, her parents are devastated, certain she has been taken. They can't bear to think about who has done this and what might be happening to their precious girl. Even worse, the police seem to see them as suspects, implying that they may have had a part in their own daughter's disappearance. Only their neighbor, Taylor, is a rock. She organizes search parties, feeds the volunteers, works night and day to help them find Brittany.

Hazel and Jamie are happily married. Or so it would seem. Behind closed doors, things are far from normal. Jamie has an unhealthy obsession, and Hazel is more worried about herself than her husband. So when Millicent injects herself into their lives, with Jamie firmly in her sights, the trio end up on a path that will end in death. Everyone has secrets. Everyone has a dark side. But who is good, who is bad, and who is going to get away with murder?

Rebecca and Sam are happily married and enjoying a typical Saturday night until a knock at the door changes everything. There is a woman outside, and she has something to say. Something that will change the happy couple's relationship forever. With their marriage thrown into turmoil, Rebecca no longer knows who to trust, while Sam is determined to find out who that woman was and why she came to their house. Desperate to save his marriage, Sam is willing to do anything to get the truth, even if it means breaking the law.

Simone used to be the woman that other women would use if they suspected that their partner was cheating. She would investigate, find out the truth, and if the men were guilty, exact revenge. But after things went wrong with one couple, Simone was forced to go into hiding. Simone is now Mary, a mild-mannered woman who doesn't raise her voice or get angry, meaning nobody would suspect her of being capable of the things she used to do for a living. But when she finds out that her new boyfriend is having an affair, it awakens in her the person she used to be.

Sarah is in a loving relationship with Paul, a man she hopes to one day marry and start a family with, until his untimely death turns her world upside down. Trying to come to terms with her loss, Sarah finds comfort in looking through Paul's old things, including his laptop and his emails. But Sarah begins to discover things about her late partner that she never knew before, and it seems he wasn't as perfect as she thought. As she unravels more about his secretive past, she ends up learning things that not only break her heart, but that the police would be interested to know too.

Jenny sits in the same seat on the same train every week, seeing familiar faces come and go. Until a chance encounter shatters her world. Sixteen years ago, Jenny survived a traumatic ordeal that left her best friend, Susie, missing and presumed dead. The world has its theories about what happened to Susie Patterson, and one of those theories points the finger at Jenny. Now she lives a quiet life, volunteering at a crisis helpline while trying to deal with her own anxiety and the true crime fans obsessed with finding her missing friend.

Nicola is returning to her family home for the Christmas holidays to spend the festive season with her loved ones for the first time in several years. But she gets a shock when she discovers that there will be an unexpected guest joining them for dinner on the big day. Their elderly neighbor, Barbara, will be present at the table too after receiving an invitation from Nicola's parents because they hated to think of the old woman spending the day alone. That is a big problem for Nicola, although she struggles to let her family members know why.

New York psychologist Will Hardy had it all - a loving family, a flourishing career, a best-selling book. Until the night it all ended in a tempest of fire and ash, leaving only Will and his 15-year-old daughter Bernadette to stand in the ruins. Haunted and grief-stricken, Will accepts an enigmatic invitation from his family’s past to begin their lives anew in the small town of Abbeville, Ohio. Meanwhile, Abbeville Chief of Police Ivy Holgrave is investigating the death of a local girl, convinced this may only be the latest in a long line of murders dating back decades.

When Sasha receives a call from her old university friend Gabby inviting her to spend Christmas at Gabby’s remote Scottish lake house, Sasha knows she shouldn’t go. Twelve years ago, on Christmas Eve, when Sasha and her five closest friends were celebrating the festive season, something truly horrific happened that would change the course of their friendship forever. Something that meant Sasha hasn’t spoken to any of them since that night.

My wedding was the perfect whirlwind of a day. The happiest I’d ever been. That was until I discovered my beloved husband, Ryan, tucked away in a compromising summer house clinch with Liza, his best friend’s wife. Reeling with this ultimate betrayal, my world in freefall, with nowhere to turn, I flee my own wedding unable to face anyone, not even my family. I just want to escape this nightmare. With our flight, to our luxury honeymoon leaving in a matter of hours, could ten blissful days of Cretan Island life, minus my cheating husband help me figure out my future?

When Tuppence was born, I thought I was complete. Even when my marriage to Leon began to falter, at least I had my baby girl to look after. Adults have problems all the time, but children have a way of making them seem so insignificant. But then Tuppence goes missing and I realize how my life has been teetering on the brink for so long. Now it's just me and my husband again, the two of us and all our problems, and we're forced to work together as a team to get our beloved daughter back.

Amy is a loving wife and mother, to her husband Nick, and her two children, Michael and Bella. It's that dedication to her family that causes her to seek help for her teenage son when it becomes apparent that he is going to fail his end of school exams.

Abi should be at home celebrating after helping to put two murderers behind bars for a sickening attack on a pensioner in his own home. Instead, she's gone missing; her phone's switched off, and her husband, Henry, is frantic with worry. But Abi's disappearance is only the start of his troubles.

I tell myself that Max couldn’t kill anyone. He’s a family man now, different to who he was before. Even so, I should go to the police right away. But I can’t. Because if I do, I’m scared they’ll start to suspect me. How much do I really know about the girl in room 12? And if the truth comes out, how far will I go to protect my precious family?