An explosion rocks Princes Street in the midst of the Edinburgh Festival. Responsibility is claimed by a group supposedly demanding political separation from Britain, but as atrocities escalate Skinner realises this is no gang of fanatics, but a highly professional team. The Fighters for an Independent Scotland want the English out of Scotland too and they're ready to back up their demands with bombings, murders and blackmail threats aimed at wreaking havoc at the Edinburgh Festival of the Arts. But the Fighters haven't reckoned with Assistant Chief Constable Bob Skinner, head of the Edinburgh CID and security adviser to Secretary of State Alan Ballantyne. Even as craven Ballantyne vows empty defiance of the Fighters, defending his principles with the blood of innocent coppers and bystanders, Skinner assembles a crack task force, carries the ball when the Secretary fumbles on the air, and wrestles with the beast within, who emerges with periodic ferocity to foil a clever, greedy scheme involving the crown jewels and Skinner's own daughter.