In the misty, moody landscapes of Wales, private investigator Hettie Shaw is no ordinary sleuth. A feisty, free-spirited femme fatale in her mid-fifties, she's spent years drowning heartbreak in the arms of younger men after the tragic loss of her husband and daughter. But when the reserved and military-trained Sir Charles reluctantly hires her to untangle a blackmail case, the unlikely duo finds themselves drawn into a far darker mystery.

When troubled Lady Gwen falls from the ominous Castle Cliff, the town whispers of suicide—until her twin brother, Lord Ambrose, is accused of murder. Determined to clear his name, Hettie and Charles dig deep into the town's secrets, uncovering a sinister web of lies, betrayals, and hidden horrors. The case takes a shocking turn when their investigation demands the exhumation of Lord Ambrose's parents, unearthing a chilling family secret.

As Charles struggles with his own turmoil—his fiancé's reckless spending—Hettie navigates a world of aristocratic corruption, seedy backstreets, and long-buried truths. But when a young girl is brutally murdered, their pursuit of justice leads them into the depths of a hidden dungeon, where they must fight for their lives against a killer determined to silence them forever.

From shadowy castles to traditional pubs, from decaying dockyards to the windswept Welsh coastline, Shadows Over Castle Cliff is a gripping murder mystery packed with intrigue, wit, and a touch of romance. As the tension mounts and the danger closes in, Hettie and Charles must rely on their wits, their courage, and even whispers from beyond the grave to survive.