The novel opens with Étienne Lantier, a young and destitute workman, wandering across the dark, flat plains of northern France in search of employment. He arrives at the Voreux coal pit near Montsou, where he meets old Bonnemort, a veteran miner whose life has been sacrificed to the earth. Étienne is eventually hired as a putter, descending into the suffocating darkness of the coal seams to toil alongside the Maheu family. Through the daily routine of the pit, the narrative exposes the brutal conditions, the grinding poverty, and the rigid hierarchy that crushes the workers.
As the months pass, Étienne becomes increasingly radicalized by the injustice around him. He absorbs revolutionary ideas and begins to discuss the necessity of a provident fund and collective resistance with his fellow miners. The situation at the mines grows more tense as the Company continually tightens its grip, lowering wages and imposing stricter rules on timbering and coal sorting. The workers' resentment simmers beneath the surface, fuelled by the contrast between their own starvation and the distant wealth of the anonymous shareholders.
The narrative follows the daily struggles, family dynamics, and forbidden romances within the miners' settlement, particularly the quiet resignation of Catherine Maheu and her complex relationship with Chaval. Despite moments of solidarity and the brief escape offered by feast days and village celebrations, the underlying misery remains constant. The tension between the starving labourers and the uncompromising management steadily mounts toward an inevitable explosion.
As the miners face harsher fines and impossible demands, the idea of a general strike takes root among them. Étienne steps forward as an energetic propagandist, organizing his mates and preparing them for the impending struggle. The novel paints a vivid fresco of collective emotion, laying the groundwork for a massive confrontation between capital and labour in the depths of the northern coalfields.
