Chen Xu is a maintenance worker at the seventh ruins of the Federation. He survives on an old welding gun and mechanical prosthetics. One day he built a wall that could cry, but it released the afterimage of the first-generation marshal that had been sealed for two hundred years. Afterimage called him 'ancestor' and gave him a dragon bone structure technique that could repair 'space cracks'. The next day, Federal Marshal Qin Ge surrounded the abandoned city with heavy troops. As soon as he saw Chen Xu, he knelt on one knee and shouted "ancestor". Chen Xu looked at his newly repaired toilet and fell into deep thought: Who am I? Qin Ge wants to take him back to the center, Lao Yu wants to steal his skills, Tie Scar wants to use him as a bargaining chip, but Bai Yuan secretly helps him change his files. When Chen Xu finally repaired an abandoned space station, he discovered the truth about the destruction of the old federation - it turned out that he was the person who shouldn't exist.
