When a much-loved Kilmarnock police constable is found beaten to death in his home, all signs point to a burglary gone wrong. But, when a second officer is slain while walking the beat, it becomes clear that something much more sinister is afoot.
Somebody is murdering cops.
Harassed by an infuriating new partner and a teenage true crime podcaster, DI Heather Filson must track down a brutal killer while tensions between the police and the public explode into violence.
With rioting breaking out across Glasgow, and running battles filling the streets, Heather's latest investigation is no longer just a murder hunt.
It's a race to stop Scotland's largest city from tearing itself apart.