On the foggy trails of Hampstead Heath, burnt-out ex-cop Arthur Grimshaw's beat is no longer CID-it's picking up after celebrity dogs. But when he stumbles upon the body of a reviled editor, face-down in the dog pond, his old life explodes back into view.
The police, led by Arthur's smug rival, call it an accident. But Arthur and his "Hounds"-a razor-sharp pensioner and a tech-savvy millennial-see the truth. Left at the scene is a single, chilling clue: a perfect, professional-grade "highwayman's hitch".
It's a dog walker's knot. And it's a message.
Dismissed as "the help" and dangerously underestimated, the trio launches their own hunt. What starts as a murder on their patch quickly unravels into a terrifying conspiracy of shadowy corporations, ruthless assassins, and a cold-blooded director who believes he's untouchable.
Now, the Hounds are being hunted. Their every move is watched, and their enemy is a corporate leviathan that has already infiltrated the police. With their lives, their homes, and their very identities on the line, can a disgraced cop, a pensioner, and a hacker do the impossible? Can they topple an empire before they're all "managed", silenced, and erased for good?