They say every marriage has its secrets. But no one sees what happens behind closed doors. And sometimes those doors should never be opened.... Sal and Charlie are married. They love each other. But they aren't happy. Sal cannot leave, no matter what Charlie does - no matter how much it hurts.

Pete never wanted another child. Before baby Erin was born, they were happy. If Natalie hadn't got pregnant, he would never have done what he did. Natalie knows things have been difficult since the surprise arrival of Erin. Life with Pete and their two other children—Emily and Zadie—has been balancing on a knife-edge. Now their home is full of guests at a party Natalie didn't want to throw—and she's about to reach breaking point. But so is her family. Because everyone has a secret that they've been hiding and when Erin suddenly disappears everyone becomes a suspect.

This is the day my life changes forever. It started so normally. The alarm went at 7am. My husband made bacon and pancakes for me and our seven-year-old daughter, the kitchen full of chatter and laughter. He gave me a quick kiss, told me he loved me, grabbed his wallet, and rushed off to work. Just an ordinary day. Until I get the call from the school. It was Tom’s turn to pick up our daughter. He must be held up for some reason. I find Tom’s phone under our bed. Now I know there’s something seriously wrong. I scroll through his messages. A text sent late last night: I KNOW EVERYTHING.

It was just a party. But it turned into a nightmare. When Rachel wakes up in a strange room the morning after a neighbour’s party, she has no memory of what happened the night before. Why did her husband leave her alone at the party? Did they row? Why are Rachel’s arms so bruised? And why are her neighbours and friends so vague about what really happened?

Cass is having a hard time since the night she saw the car in the woods, on the winding rural road, in the middle of a downpour, with the woman sitting inside - the woman who was killed. She's been trying to put the crime out of her mind; what could she have done, really? It's a dangerous road to be on in the middle of a storm. Her husband would be furious if he knew she'd broken her promise not to take that shortcut home. And she probably would only have been hurt herself if she'd stopped.