A poet-detective infiltrates a council of anarchists, only to discover that the organization is far more complex and bizarre than he initially imagined. Gabriel Syme, a man dedicated to maintaining order, joins a secret police force tasked with dismantling a group of seven anarchists who use the names of the days of the week. As he assumes the identity of 'Thursday,' he finds himself caught in a series of surreal confrontations and shifting allegiances. The narrative operates as a metaphysical thriller, utilizing a dreamlike logic to challenge the protagonist's perceptions of reality and authority.

Discussion often centers on the novel's unique blend of detective fiction tropes and deep philosophical inquiry. Readers frequently highlight the disorienting atmosphere and the author's ability to maintain a sense of mystery while simultaneously mocking the seriousness of his characters. Critics often note that the work functions as a complex allegory, though interpretations of its ultimate message vary widely among scholars. The pacing is frequently described as frantic and dreamlike, which serves to reinforce the central themes of instability and the search for truth. Many readers appreciate the stylistic flair and the imaginative leaps that define the narrative structure throughout the book.