A notice from the Galaxy Cultural Heritage Administration registered Earth as the "Seventh Native Civilization Site." However, in the assessment report of the Management Bureau, humans were labeled as "ecological pollutants added illegally in the late period" and it was recommended to be cleaned up within a time limit. On the day the countdown started, it was an ordinary early morning. The administrative disc suspended above the city cast a shadow, and all the screens simultaneously played "Cleaning Notice." History student Su Yuan discovered an encrypted fragment of the earth's "true history" in the chaos. The documents show that human beings are not "additions", but the spark of native civilization that has been deliberately "forgotten". He must prove to the entire galaxy that we are not pollution before the global "cleanup" process begins. We are the legacy itself.