'The Heavenly Twins,' written by Sarah Grand, was a novel that shocked its late-Victorian audience, but which still remains largely unheard of today. Grand's novel, quite polemical in its time, addressed ideas of female sexuality and education, among other topics. Grand herself meant the work to be predominantly didactic, always stressing that it is most often what a woman does not know that can most hurt her. Throughout the work, Grand makes constant references to items of her period, some literary, some political, some even scientific. It is these allusions that give the novel an additional richness and depth; needless to say, readers unfamiliar with the many references may overlook any wit or wisdom Grand has intended to impart with their use. Until now, no critical edition of 'The Heavenly Twins' has existed. The annotations within are not only meant to serve as a reading companion to Grand's work but, it may be hoped, will lend to a further understanding of the world from which the author is writing from.