The murder of a prominent mill owner in 1831 sets in motion a series of events that entangle the Barton family in a web of suspicion and social unrest. Mary Barton navigates the harsh realities of Manchester during the late 1830s, caught between the desperate struggles of the working class and the personal consequences of her father's radical associations. As she matures, she faces the unwanted attention of a wealthy mill owner's son, forcing her to reconcile her personal desires with the political turmoil surrounding her. The narrative, presented in a third-person perspective, examines the friction between labor and capital through the lens of individual lives. The story unfolds against the backdrop of economic depression, where the physical environment of the industrial city dictates the survival of its inhabitants.

Discussion often centers on the author's ability to humanize the plight of the working class during the Industrial Revolution. Readers frequently highlight the stark contrast between the domestic sphere and the harsh public realities of the Manchester mills. Critics often note the balance between the novel's function as a social document and its development of complex, flawed characters. The narrative pacing is frequently described as deliberate, allowing for a thorough examination of the socio-economic pressures that drive the plot forward. Many readers appreciate the nuanced portrayal of the protagonist's growth as she moves from youthful innocence to a more mature understanding of her environment.