Based on a novel by Richard Llewellyn, a family of Welsh coal miners experiences hardships through the eyes of the youngest son.
Huw Morgan (Roddy McDowell) recalls his childhood in Wales. Coal miners sing as they walk home. After dinner his father Gwilym Morgan (Donald Crisp) gives out spending money. Bronwyn (Anna Lee) arrives and weds Ivor Morgan (Patric Knowles). They celebrate. Mining wages are lowered because of unemployed iron workers. Gwilym opposes a union, and his sons Owen (James Monks), Gwilym Jr. (Evan S. Evans), and Ianto (John Loder) leave the house. Miners strike for 22 weeks. In a snow storm Gwilym's wife Beth Morgan (Sara Allgood) defends her husband. She falls into icy water with Huw, and they are rescued. Minister Gruffydd (Walter Pidgeon) encourages Huw, and Angharad Morgan (Maureen O'Hara) invites him to supper. In bed Huw reads books. Huw's mother recovers, and miners sing for her as her four sons come home. Ianto criticizes deacon Cyfartha (Barry Fitzgerald), but Gruffydd favors the union for justice. He tells Angharad she is a queen. Gruffydd settles the strike; but some have no jobs. Owen and Gwilym Jr. ask for their share of the money to go to America. Ivor gets a summons for his choir to sing before the Queen. Gruffydd carries Huw up a hill, gets him to walk, and advises prayer.
In church deacon Cyfartha wants to punish a woman for having a baby in sin. Angharad objects and walks out after her, followed by Gruffydd. The mine owner Evans calls on Gwilym so that his son can court Angharad; but she goes to Gruffydd, who says he is too poor for her. She kisses him and leaves. Angharad weds young Evans. Gruffydd tutors Huw for an exam, and he attends a national school. Huw fights a bully and comes home bloody. Gwilym and his wife disagree over whether Huw should fight. Gwilym has Dai Bando teach Huw how to box. Huw boxes well but is caned by his teacher Jonas (Morton Lowry). Dai Bando gives Jonas a lesson in front of his class and knocks him out.
A whistle is heard, and Gruffydd learns that Ivor was killed in the mine; but his wife Bronwyn has a son. Huw says he wants to be a collier and goes to live with Bronwyn. Huw works in the mine. Ianto and Davy (Richard Fraser) are discharged and leave. Angharad comes back from Capetown alone, and Huw goes to her big house. Angharad asks about Gruffydd. Mrs. Nichols has been there 37 years and spreads gossip about Angharad and Gruffydd. In the mine Huw fights mocking boys. Gruffydd announces in church he is leaving, castigates hypocrites, and tells Huw he wanted to lead an army of truth for liberation. He gives Huw his watch. Whistling signifies a cave-in. Gruffydd sees Angharad and goes down with Dai Bando and Huy to search for Gwilym. Huw finds his father stuck in water, but he dies. In the final scene Huw walks with his father in the hills and sees his five brothers.
This drama reveals the harsh conditions of coal miners
about 1890. A minister gives them inspiration but is too poor
to marry the woman who loves him.