A young, ambitious astronomer and a high-born woman navigate the social and professional consequences of their clandestine marriage. Lady Viviette Constantine, a woman of higher social standing, finds her life altered when she encounters Swithin St. Cleeve, a talented but impoverished astronomer working in a remote tower. Their relationship faces immediate pressure from rigid Victorian class structures and the logistical challenges of maintaining a secret union. The narrative explores the tension between intellectual pursuit and the constraints of societal expectations, often highlighting the isolation inherent in their chosen path. The story is presented through a third-person perspective that emphasizes the vastness of the cosmos against the smallness of human social concerns.

Readers frequently highlight the novel as a departure from the author's more famous rural tragedies, noting its specific focus on the intersection of science and romance. Discussion often centers on the characterization of Viviette and the ways in which her social position dictates the trajectory of the plot. Critics often point to the atmospheric use of the tower setting as a defining feature that elevates the narrative beyond a standard domestic drama. The pacing is described as deliberate, allowing for a thorough examination of the protagonists' internal motivations and the external pressures they face. Many readers appreciate the intellectual depth provided by the astronomical motifs, which serve to ground the emotional stakes in a broader, more existential context.