One perfect summer day, mother of two Alice walks into the sea... and never comes back.

Her daughters - loyal but fragile Lily, and headstrong, long-absent Marietta - are forcibly reunited by her disappearance.

Meanwhile, with retirement looming, DI Fox investigates cold cases long since forgotten. And there's one obsession he won't let go: a tragic death twenty years before.

Can Lily and Marietta uncover what happened to their mother? Will Fox solve a mystery that has haunted him for decades? As their stories unexpectedly collide, long-buried secrets will change their lives in unimaginable ways.

A gripping and emotional new thriller perfect for fans of Cara Hunter, Heidi Perks, Claire Douglas and Linda Green.