A dying Dr. Mark Langer finds a frightened microbiologist who has developed a cure for age. Rejuvenated by genetic engineering, Mark takes over the task of negotiating with the world who should win the treatment and how civilization must cope with the prospect of more overpopulation.
He battles an assault on the White House, near assassination, and civil wars in his desperate attempt to stabilize a world upset by the advent of eternal life. His character changes via new neurons that replace those that have died over his long lifetime. He also rediscovers love and the many other joys of youth.