Denise Baudu, a young woman from the provinces, arrives in Paris and finds herself caught in the rapid expansion of a colossal department store that threatens to destroy the traditional small businesses of the neighborhood. Denise must navigate the harsh social hierarchy and predatory labor practices of the store while resisting the advances of its ambitious owner, Octave Mouret. As she climbs the ranks, she observes the transformation of consumer habits and the erosion of old-world values in the face of aggressive capitalism. The narrative employs a third-person perspective to detail the mechanical operations of the store and the psychological shifts of its employees and patrons. The physical environment of the store acts as a central character, exerting pressure on the lives of those who work within its walls.

Readers frequently highlight the meticulous detail Zola employs to describe the architectural and economic mechanics of the department store. Discussion often centers on the tension between the protagonist's moral integrity and the seductive, often destructive, nature of the retail environment. Critics observe that the work serves as a significant historical document regarding the evolution of capitalism and urban life in Paris. The pacing is noted for its deliberate, observational style that mirrors the relentless growth of the store itself. Many readers find the exploration of class relations and the changing status of women in the workforce to be particularly relevant to modern economic discourse.