The end of the world does not come from war or viruses, but from an irreversible cosmic event (such as an approaching supernova explosion, strange radiation produced by a galaxy collision), and the earth's surface environment will become completely unsuitable for the existence of known carbon-based life. Humanity's only option is to engage in "forced evolution": to transform itself on a large scale through radical genetic engineering technology to adapt to the new hellish environment (such as high temperature, high pressure, sulfide atmosphere, underground ocean, etc.). The new humanity is vastly different from the old humanity in appearance, physiology, and cognition. Protagonist: Kai, a "modifier" whose body is modified to adapt to a new world filled with acidic atmosphere and geothermal pits. He sees himself as the inevitable form of humankind's continuation, but he still has romantic imaginations about the old world derived from textbooks and data disks.
Story summary: Several generations later, the "reformed people" established a new civilized order in the new world. However, an ancient generation ship from the pre-Cataclysm era (or a dormant old human refuge) is suddenly discovered/awakened. The inhabitants are pure, unmodified "original people". The appearance of the "original man" caused an uproar. Some of the modified people regard them as "ancestors" and living fossils, and are eager to communicate with them and learn the lost history and culture; others regard them as "inferior" and "backward" species, whose existence itself is a challenge to the legitimacy of the modified people, and advocate isolation or even elimination. Kai is forced to take charge of making first contact with the Original Man. He finds himself caught between two ideologies while dealing with the "original man's" fear of unfamiliar surroundings.
