How well do you really know the people closest to you? Aria Miller used to think she had the perfect life, but now that the honeymoon phase is all but a distant memory, she can't shake the feeling her perfect life is a sandcastle waiting to collapse. Recently she's felt a prickle of anxiety when her husband Ethan says he has to work late. She's trying to shake the feeling that he's been lying. After all, trusting men has never worked out well for Aria . . . But sweet, kind Ethan has never given her a reason not to trust him, has he? Perhaps the stress of trying for a baby is finally getting to her, recently she swears she feels someone is watching her as she grabs her morning decaf coffee. Then, during a girls' night that was supposed to take her mind off things, her best friend Isla is brutally murdered in a dark bathroom bar. Aria is still reeling from the shock when the text arrives: How well do you know your husband? And suddenly, amid a police investigation and Ethan's increasingly strange behaviour, Aria is forced to question everyone around her - including herself. He said he loved me. He said I had nothing to worry about. What else don't I know about my husband's lies?