Based in the mid-19th century it tells the story of the Standish family, who moved from the coalfields of Lancashire to the slate quarries of North Wales. The eldest Standish boy, Tommy, was something of a changeling: he desired a different life and ruthlessly went in pursuit of his dream of the grandeur and riches of the landowners' class. His ambitions realised, Tommy, is intent on higher profits even though it risks the lives of the quarrymen. Joe, his father, fights for a union to secure fairer conditions for the men. The quarrymen are close to becoming victims as the war between father and son escalates.