Émile Zola left an archive the size of a world: thousands of manuscripts covering novels, plays, articles, and short stories. This essay invites readers into his studios from Paris to Médan, to follow the genesis of his sprawling series, informed by science, the arts, and literary tradition. From preparatory research to final variations, his was a process combining rigor and creative brilliance. In the print media ferment of the 19th century, his manuscripts became public objects. This portrait reveals a modern, visionary Zola, ever a source of inspiration.