Following a nuclear war, a small group of scientists, who had planned ahead and built a shelter, found that the residual radiation had made them sterile. To prevent the extinction of the human race, they experimented with cloning and eventually created two clones who were fully functional except they needed microchips to make their brains function properly. This is the story of Johnny and Gwen and their journey after accidently discovering they were clones and running away. They meet Harry, who mentors and trains them in their humanity, teaching them how to survive in this new post-nuclear world. Eventually, they return with Harry to their original home with a new maturity and a new future.