In the half century since Watson and Crick's discovery of the double helix, genetic scientists have grafted onto the tree of knowledge a body of new science whose growth has slipped the bonds of the divine and nature. Investigative journalist Elaine Dewar chronicles the lives, discoveries, and feuds among these modern biologists, exploring how they have crafted the tools to alter human evolution with unforeseeable, promising, and frightening consequences the rest of us are just beginning to glimpse. Dewar travels the world in the wake of Charles Darwin and his intellectual descendants, telling the story of Frederick Sanger who learned how to sequence genes and won two Nobel prizes; and of the computer scientists who put the human genome on the worldwide web. She visits corporations determined to turn cloned sheep into pharmacies, resurrect prize cattle from the dead; and transplant human genes into mice—ultimately striving for immortality while keeping investors happy. As Dewar narrates these tales, we learn how biologists make breakthroughs: tearing mice, worms, flies, and human eggs apart, twining disparate animal cells and genes together—creating clones and chimeras as outlandish as any sphinx from the realm of mythology.