This book is the only scientific biography of the Nobel Prize–winning Indian American chemist, Har Gobind Khorana. It begins with the story of Khorana’s origins in poverty in rural India and how he manages to emerge from that to be trained in chemistry in Britain and Switzerland before immigrating to Canada and the United States. Science was the dominant focus of Khorana’s life, and his biography is treated chronologically in conjunction with his scientific career. The book explains in detail Khorana’s most important scientific achievements, his role in deciphering the genetic code (the reason for his Nobel Prize), the first synthesis of a functional gene in the laboratory, the elucidation of the idea behind the PCR technology that has since become ubiquitous in biotech, and his seminal studies of how structure determines the function of biological macromolecules in membranes. Finally, it focuses on his scientific legacy, and what his career means for future generations of scientists.