The waters surrounding an island become contaminated by chemical dumping, and people who eat fish caught in those waters become deformed and violent.

Set in Manchester, heartland of England's industrial north, Don Starling escapes from jail becoming England's most wanted man. Ruthless villain Starling together with his cronies engineered a robbery that resulted in the violent death of a young girl. Detective Inspector Martineau has been assigned to hunt him down and bring him in. From seedy barrooms, through gambling dens the trail leads to an explosive climax high on the rooftops of the city.