More than two hundred years ago, a virus was accidentally leaked and mutated, turning most people around the world into zombies. In the last days of mankind, a group of people who call themselves priests stand out. They claim to have inherited the power of the Creator God and can control the elements in the heaven and earth. The priests used their powerful power to fight against the evolving and multiplying viruses, but ultimately failed. When the last piece of land was about to be lost, the remaining humans were forced to board Noah's Ark and drifted in the sky away from the ground. Two hundred years after Noah's Ark left the ground, humans finally decided to return to the ground again and take back their former home.