When Joe Lynch stumbles across his wife driving into a hotel car park while she's supposed to be at work, he's intrigued enough to follow her in. And when he witnesses her in an angry altercation with family friend Ben, he knows he ought to intervene. But just as the confrontation between the two men turns violent, and Ben is knocked unconscious, Joe's young son has an asthma attack - and Joe must flee in order to help him.

When he returns, desperate to make sure Ben is OK, Joe is horrified to find that Ben has disappeared. And that's when Joe receives the first message... Gripping, unputdownable and packed with twists and turns from the first page to the very last, this stunning thriller will make you question whether we can ever really trust the ones we love...