Morfa Halen is a tight-knit Welsh town precariously nestled between towering mountains and a fast-encroaching sea that threatens its very existence. As a once-in-a-generation storm begins to gather far out at sea, former detective turned teacher Jackie Ellis discovers the body of her 8-year-old pupil, Cefin, seemingly drowned. The discovery sends shockwaves through the community, reviving the ghost of an unsolved cold case that rocked the town three years prior - the disappearance of Jackie’s niece, Nessa, which cost her career.

A veteran beat cop and teenage girl fall to their deaths from a tower block in south-east London, leaving a five-year-old boy and rookie police officer Lizzie Griffiths on the roof, only for them to go missing. Detective Sergeant Sarah Collins is drafted in to investigate, working to find Lizzie before she comes to serious harm, but also to uncover the truth behind the grisly tower block deaths.

A man in the midst of a mid-life crisis moves his family to a remote Scottish village, only to find himself entangled in a dangerous friendship with a sinister neighbour.