Triumphantly true to form, Powers continues the densely layered and intricate plotting found in his earlier novels (Prisoner's Dilemma, Three Farmers on Their Way to a Dance) in this stunning epic that delves into molecular genetics, music, and information science, eloquently combining the mysteries of love and the passionate pursuit of knowledge. In a manner reminiscent of A.S. Byatt's Possession, a capable young reference librarian renews her sense of purpose as she and a computer technician/art-historian come together in seeking to recover the past of his co-worker Stuart Ressler, a brilliant older man wasting his talents as the night supervisor in a Brooklyn data- processing facility--and soon unmasked as one of the brightest hopes in genetics in the 1950's who vanished from the field after a promising start. The interweaving threads of narrative reconstruct a tragic affair between Ressler the scientist and a married colleague; a similarly electrifying and devastating relationship between the two sleuths; the perilous path of science as it grapples with the fundamental patterns of life; and the librarian's own obsession with the secrets of genetic coding, initiated in despair after learning of Ressler's death from cancer. Ranging in detail from genetic formulas to musical ones (with the title a typically witty reference to both Bach's variations and the Poe short story), replete with scintillating characters, especially the oddball team of scientists gathered to crack the code on a midwestern campus in the 50's, and structurally as well-tempered as a Bach fugue, the harmonious interplay between personal and scientific drama is both challenging and exquisite. A formidable masterpiece, deeply vital and sparkling in its many facets, whimsical in its prose yet precise in its elucidation- -rewarding in every sense but, in particular, a profoundly moving love story.