After her bittersweet success in series one, Karen has been promoted to Detective Inspector and seemingly given the authority she has long been fighting for. Just as she’s getting into the swing of her powerful new role, she is assigned an infamous unsolved case that will put her under intense scrutiny from her boss, from the media, and ultimately, from sinister forces that would rather the past stayed in the past.
　　The 1984 case of Catriona and Adam Grant has confounded investigators and intrigued the public like no other. Catriona, the charming young heiress to a vast oil fortune, and her two year old son Adam, were brutally kidnapped at gunpoint outside a fish and chip shop in Fife. The ransom notes that followed stirred up an uncontrollable press storm, but when the culprits fell silent, the police faltered, and Catriona and Adam were never seen again.
　　Now, a man’s body has been discovered, with indisputable links to the original kidnap. With the first piece of evidence in decades, Karen must assemble an unbeatable team alongside her sincere and lovable sidekick DC Jason ‘Mint’ and the brilliant – but romantically complicated – DS Phil Parhatka. With the international renown of the kidnap and the constant pressure from Catriona’s father, Sir Broderick Grant, the team take on the biggest challenge of their careers to date. As Karen delves deeper into what happened in the autumn of 1984, political grudges and painful secrets reveal themselves, and it soon becomes clear… the past is far from dead.