Huw Morgan (Roddy McDowall), the academically inclined youngest son in a proud family of Welsh coal miners, witnesses the tumultuous events of his young life during a period of rapid social change. At the dawn of the 20th century, a miners' strike divides the Morgans: the sons demand improvements, and the father (Donald Crisp) doesn't want to rock the boat. Meanwhile, Huw's eldest sister, Angharad (Maureen O'Hara), pines for the new village preacher, Mr. Gruffydd (Walter Pidgeon).