The quest for immortality has inspired humankind since the dawn of civilization. Diverse ancient myths and religious stories tell of miracle drinks that bestowed eternal life on the gods, while kings across the ages have quested for comparable real-life elixirs. Chinese emperors, drawn by the promise of eternal life, swallowed concoctions containing everything from gold to arsenic and mercury, an often lethal cocktail. More recently, the late North Korean dictator Kim Il-Sung purportedly received transfusions of blood from young donors in hopes of extending his life. All these failed attempts at achieving longevity underscore the harsh truth that death will, inevitably, overtake us. Nevertheless, a century of research has brought us closer than ever to understanding what causes aging and what might be done to postpone its ultimate outcome.