In a distant future where the sea levels have risen dramatically, fertile land has become a rare luxury. Humanity has retreated to towering, multi-layered cities built on the last mountaintops, with the wealthy living high above, basking in sunlight and fresh air, while those in the Lower City survive in cramped, shadowed spaces, starved of nature and hope.

In the Lower City, rebellion simmers. An underground resistance known as the "Liberation Front" has arisen to challenge the oppression from above. Among its ranks is Chu Tianzhu, a senior rebel leader with a fierce will and a hidden dream of freedom. By a stroke of fate, he stumbles upon a mysterious artifact—an object that grants him the ability to travel between his own bleak world and a strange, untouched world steeped in an ancient agrarian lifestyle.