Set in the twenty-first century, it was influential on the development of English science fiction, particularly on H.G. Wells (see "The Time Machine," "The Island of Dr Moreau," and "The Invisible Man"), Olaf Stapledon and, less obviously, Arthur C. Clarke, particularly "Childhood's End." Central to the book's philosophical approach is a rejection of the romanticism of Lord Byron, whom she knew well, and her late husband. It blends astute political observation, a complex tale of doomed love and obvious portraits of Percy Bysshe Shelley and Lord Byron into its subtle, melancholy mix. It is beautifully written and rewards both initial reading and, even more, re-reading.