The novel's central character is Étienne Lantier, previously seen in L'Assommoir (1877), and originally to have been the central character in Zola's "murder on the trains" thriller La Bête humaine (1890) before the overwhelmingly positive reaction to Germinal persuaded him otherwise. The young migrant worker arrives at the forbidding coal mining town of Montsou in the bleak area of the far north of France to earn a living as a miner. Sacked from his previous job on the railways for assaulting a superior, Étienne befriends the veteran miner Bonnemort, who finds him somewhere to stay and gets him a job pushing the carts down the pit. Étienne is portrayed as a hard-working idealist but also a naïve youth; Zola's genetic theories come into play as Étienne is presumed to have inherited his Macquart ancestors' traits of hotheaded impulsiveness and an addictive personality capable of exploding into rage under the influence of drink or strong passions. Zola keeps his theorizing in the background and Étienne's motivations are much more natural as a result. He embraces socialist principles, reading large amounts of working class movement literature and fraternizing with Souvarine, a Russian anarchist and political émigré who has also come to Montsou to seek a living in the pits. Étienne's simplistic understanding of socialist politics and their rousing effect on him are very reminiscent of the rebel Silvère in the first novel in the cycle, La Fortune des Rougon (1871).
While this is going on, Étienne also falls for Maheu's daughter Catherine, also employed pushing carts in the mines, and he is drawn into the relationship between her and her brutish lover Chaval, a prototype for the character of Buteau in Zola's later novel La Terre (1887). The complex tangle of the miners' lives is played out against a backdrop of severe poverty and oppression, as their working and living conditions continue to worsen throughout the novel; eventually, pushed to breaking point, the miners decide to strike and Étienne, now a respected member of the community and recognized as a political idealist, becomes the leader of the movement. While the anarchist Souvarine preaches violent action, the miners and their families hold back, their poverty becoming ever more disastrous, until they are sparked into a ferocious riot, the violence of which is described in explicit terms by Zola, as well as providing some of the novelist's best and most evocative crowd scenes. The rioters are eventually confronted by police and the army that repress the revolt in a violent and unforgettable episode. Disillusioned, the miners go back to work, blaming Étienne for the failure of the strike; then, Souvarine sabotages the entrance shaft of one of the Montsou pits, trapping Étienne, Catherine and Chaval at the bottom. The ensuing drama and the long wait for rescue are among some of Zola's best scenes, and the novel draws to a dramatic close. Étienne is eventually rescued and fired but he goes on to live in Paris with Pluchart.
The title, Germinal, is drawn from the springtime seventh month of the French Revolutionary Calendar and is meant to evoke imagery of germination, new growth and fertility. Accordingly, Zola ends the novel on a note of hope and one that has provided inspiration to socialist and reformist causes of all kinds throughout the years since its first publication:
"Beneath the blazing of the sun, in that morning of new growth, the countryside rang with song, as its belly swelled with a black and avenging army of men, germinating slowly in its furrows, growing upwards in readiness for harvests to come, until one day soon their ripening would burst open the earth itself."
By the time of his death, the novel had come to be recognized as his undisputed masterpiece. At his funeral crowds of workers gathered, cheering the cortège with shouts of "Germinal! Germinal!". Since then the book has come to symbolize working class causes and to this day retains a special place in French mining-town folklore.
Zola was always very proud of Germinal and was always keen to defend its accuracy against accusations of hyperbole and exaggeration (from the conservatives) or of slander against the working classes (from the socialists). His research had been typically thorough, especially the parts involving lengthy observational visits to northern French mining towns in 1884, such as witnessing the after-effects of a crippling miners' strike first-hand at Anzin or actually going down a working coal pit at Denain. The mine scenes are especially vivid and haunting as a result.
A sensation upon original publication, it is now by far the best-selling of Zola's novels, both in France and internationally. A number of exceptional modern translations are currently in print and widely available.