For most of human history, understanding the basis of cancer posed a grave scientific challenge. For lack of knowledge of the DNA double helix, scientists were unable to understand the genetic roots of cancer, and subsequently they were unable to develop effective methods of treatment. In the early 1950s, scientists were on the verge of discovering the DNA double helix and unveiling cancer as a genetic disease. Stumped by the uncertainty regarding the shape of the DNA bases, the structural and functional "soul" of DNA, the male-dominated scientific establishment - from James Watson and Francis Crick to Linus Pauling - proposed models of DNA that were, in effect, inside out. In contrast, a woman, Sister Miriam Michael Stimson, OP, an Adrian Dominican sister and chemist, dared to imagine a solution to the DNA base problem. Using potassium bromide (KBr) to prepare the DNA bases for analysis by infrared spectroscopy, Sister Miriam Michael successfully developed a chemical method that affirmed the structure of the DNA bases and of the double helix itself. The Soul of DNA recounts, for the first time, the role of Sister Miriam Michael Stimson, OP, in the discovery of the DNA double helix