The novel is a bleak and realistic portrayal of coal miners' lives in 19th century France. The protagonist, a young man who starts work in a mine, becomes embroiled in the hardship and exploitation faced by the workers, leading to his involvement in a strike. The story explores themes of poverty, social injustice, and the struggle for workers' rights, while also providing a detailed depiction of mining life, from the dangerous work conditions to the close-knit communities.