Her best friend is dead.

Emma and Ariella, neighbours in one of Sydney's most exclusive suburbs, appear to have it all - perfect homes, perfect husbands, perfect lives. But they both know dark secrets lurk beneath the surface and shallow waters can't hide Ariella's. Now she has been found murdered.

Her daughter filmed the killing.

Not knowing what she's filmed, Emma's daughter Kiki innocently uploads footage of Ariella's brutal death. Emma fears the worst - the killer will know what she and Kiki have seen. Their safe suburban lives no longer exist.

Her husband knows more than he's revealing.

Emma's husband Charles forces the family to leave their perfect life and escape on their yacht. His dangerous plan to flee means Emma is trapped and desperately seeking answers. What are they hiding from? What did Ariella have to confess? And who else knows Emma's own secret?

Her secret isn't safe and neither is she.