Police stations are outdated, and AI's make more efficient detectives, or so says a UK Home Office determined to make cuts.

When the sole witness in a trafficking case is discovered brutally murdered, a brass horseshoe forced between his teeth, Detective Sergeant Rex King is summoned back to London and into a labyrinth of memory, music, and political unrest. From The Clash's ragged 1985 busking tour to the fractured legacy of the anti-nuclear movement, Rex follows threads that tug uncomfortably at his own history – echoes he can't quite place, shadows that refuse to settle.

When Rex's boss, DCI 'Lollo' Lawrence, suddenly disappears, and long-buried papers from the Miners' Strike surface, he must work alongside a sharp young detective, a seasoned former soul boy, and the National Crime Agency's unsettlingly brilliant new AI. Yet the deeper he travels, the more he finds the investigation folding back on him: professional loyalties strained, personal relationships tested, and accusations from his undercover past threatening to unmake him.

Two murders, one 'misper' and a force under fire – has former 'spycop' DS Rex King finally met his match?