They find her just as the sun is beginning to rise in the early morning mist. They had begun at dawn, the group of searchers keen to get going. A missing child spurred everyone on. In the end, it was a flash of color, a bright neon pink that caught her eye. They had been looking for pink.

Nothing tests your faith like being a mother. The first time your children walk to school alone, their first sleepover, when they finally fly the nest. As a parent, you have to believe that everything will be ok.

It's why, when Lydia’s 16-year-old daughter Zoe goes on a school camping trip, she has no idea of the horrors that will unfold. It's why, when Lydia gets a call saying that her daughter has disappeared, she refuses to give up.

As she searches the mountains, her voice hoarse from calling Zoe’s name, she imagines finding her. She envisions being flooded with relief as she throws her arms around her child, saying, "You gave us such a scare!" She pictures her precious girl safely tucked in bed that evening.

It's why, when they find Zoe’s body, Lydia can barely believe it. It is unthinkable. Her little girl has gone.

Something terrible happened, she is sure of it. Something made Zoe get out of her sleeping bag in the middle of the night, walk out of the warmth and safety of the cabin, into the darkness of the mountains. Driven by the memory of her youngest child, Lydia needs to find out the truth. What kind of mother would she be if she didn’t?

A heartbreaking, redemptive and beautifully crafted novel which brings to life a mother's worst nightmare, questioning how well we ever really know the people we love the most. Fans of Jodi Picoult, Kerry Fisher and Liane Moriarty will be blown away by this stirring, unforgettable tale.