Set in late-19th-century London, the novel follows an agent involved in espionage for an unnamed foreign power amid a small circle touched by anarchist agitation. The book traces the effects of political plotting and covert operations on ordinary lives, especially relationships marked by dependency and vulnerability.

A woman embedded in high society navigates the pressures of reputation, money, and marriage as private desires and public judgment intersect. The immediate pressure is how social expectations and limited economic choices shape personal decisions and lead to moral and material consequences.