Venki Ramakrishnan, recipient of the Nobel Prize in Chemistry and former president of the Royal Society, takes us on a riveting journey to the frontiers of biology, asking whether we must be mortal. Covering the recent breakthroughs in scientific research, he examines the cutting edge of efforts to extend lifespan by altering our physiology. But might death serve a necessary biological purpose? What are the social and ethical costs of attempting to live forever?