Scientists on a distant planet managed to fulfill humanity’s long-standing dream of extending people’s lives. But every medal has a downside. Having made their bodies immortal by influencing a group of genes responsible for the aging of the body, they thus disrupted the natural balance and, over time, lost their reproductive ability, which ultimately brought the entire civilization to the brink of extinction. Any attempts to restore the lost function were unsuccessful. The last hope was an accidentally discovered planet inhabited by people biologically compatible with their own organisms, but on which the “Stone Age” reigned.