"L'Oeuvre au Noir" is at the same time a study of the Renaissance and a picture of that turbulent era as seen through the eyes of a poet. Unlike most fiction on the same period, Mme. Yourcenar's novel depicts in depth all the complexity of the Renaissance, its theological disputes, military campaigns, social conflicts, the clashes between faith and science….

What gives this fateful story a singular dimension is its high intellectual content. True to the searching spirit of his times, Zenon constantly probes the destiny of man and investigates the universe; his attempts at the transmutation of elements (called "the Black Work" by alchemists) determine his mental attitudes. Yet his skepticism, his whole Weltanschauung (rendered by Mme. Yourcenar in brilliant dialogues and sophisticated meditations) have an utterly modern ring. "L'Oeuvre au Noir," written in the compact, poetic language so typical of Mme. Yourcenar, is a stirring, unusual and often disturbing experience for the contemporary reader. (p. 35)