This novel’s tone is one of constant societal critique. The narrator takes an attitude that's unmistakably dark and, at times, scathingly satirical. They remain detached from the storyline, although there are one or two moments early in the novel where they seem to slip into the first person when criticizing Verloc. In general, the tone is gloomy, ambivalent, and pessimistic.
The Secret Agent’s portrayal of institutions and authority figures is deeply cynical. The police, as Conrad depicts them through characters like Chief Inspector Heat and the Assistant Commissioner, are shown to be more interested in bureaucratic rules and preserving order than genuine justice. Their interactions, especially in scenes where they deliberate over procedures, are so absurd at times that they seem like pantomime. The tone of the narrator here is not just critical but verges on the farcical, showcasing the inefficacies of the criminal justice system in 1880s England.
Conrad's treatment of the novel’s anarchists, especially the Professor, further adds layers to the tonal complexity. While the narrative voice could have vilified them, it instead delves into their individual ideologies. This in itself is still a critical move: Conrad portrays them as both nuanced thinkers and as unwitting byproducts of the very society they seek to disrupt. They aren't stupid, so they are responsible for their actions.
This derisive tone is relatively consistent until the later parts of the novel. It changes notably when the narrator begins to describe the events surrounding Stevie's death and its bloody aftermath. Here, Conrad's tone changes to one of somber reflection, as the novel shifts its focus to the human cost of inept government control and failed terrorist actions. Winnie Verloc's emotions—and her eventual, drastic actions in particular—are approached by the narrator with sensitivity and seriousness.
