Rachel's current troubles are only the latest in a litany spanning dozens of countries, scores of marriages, hundreds of children and 2,000 years. Only one person shares her immortality: an illicit lover who pursues her through the ages. But when her children develop technologies that could change her fate, Rachel must find a way out. From ancient religion to the scientific frontier, Dara Horn pits our efforts to make life last against the deeper challenge of making life worth living.