Met detective Eden Driscoll never wanted a child, but when his estranged sister vanishes from her sailboat, he is asked to look after her son Finn – the nephew he hadn’t even known existed. Resettled in the seaside town of Teignmouth, Eden adjusts to his newfound parenthood. Then Finn disappears from school, and Eden knows something is dreadfully wrong. When Eden's sister's body is finally found, floating in the sea, local police rule her death an accident, but Eden isn’t convinced. She was an experienced sailor and would never sail without a life jacket. Eden starts searching his sister’s life for answers, and what he discovers changes everything.