Jules Winters comes from a desiccated community, Eldorado Springs. He meets a young woman and falls in love on the same day his only friend has been condemned to prison. Gradually, Jules feels like an exotic animal kept in a menagerie. Reflecting Cato the Elder’s decision that a free man’s ultimate decision is suicide, Jules decides to sacrifice himself and save those he left behind. He extracts his humanity piece by piece and rebuilds himself as a robot. In the consequent loss of his own humanity and those he loves, he ultimately saves humanity by a twist on natural selection. To save humanity, he must terminate it.