Due to the destruction of nature, the disruption of ecosystem, and also massive wars using nuclear bombs and biological weapons since 20 centuries, the earth fell into ruins. The ground was collapsed and polluted, and many kinds of plants and animals became extinct. The earth encountered the 6th mass extinction: The Big Six. During the time, humans built the aero police to save endangered species. In this isolated city in the sky, various animals evolved over the years through genetically modified mating. As a result, they started walking on two legs and acquired language. Today, they have built a civilization and lead peaceful lives. No one thinks of the outside, the terrestrial world any more―― One day, kids on the aero police find an unknown seed from the outside. And their adventure in the unseen terrestrial world starts! ――Without knowing that once they go down to the ground, they will never be able to come back… (Source: STUDIO 4℃) Note: UTOPA is one of four Anime Tamago 2016 young animator training projects.