Etienne (Jean Sorel) is a young man who seeks work in the coal mines of South France. After experiencing the harsh working conditions, he becomes a labor activist and tries to organize a strike to improve wages and conditions. He is tormented by the mine owner, whose promiscuous wife steps out on him at will. Etienne falls in love with the daughter of a fellow miner, but her loyalty to her father and fear for the loss of his job makes her initially unresponsive to his romantic leanings. The film version of the novel by Emile Zola loses much of the poignant political commentary of the original text. Although the strike is not entirely successful, it paves the way for new considerations of worker's rights.