A biochemical leak codenamed "Red Fog" swept across the world. Half of humanity mutated into bloodthirsty zombies "walking zombies" within seventy-two hours, and the city became a hunting ground of steel and flesh. Zhang Bing, a retired soldier, lost his younger brother who had just retired from the army and returned home for reunion in the chaos. With the military dagger left behind by his younger brother and the unsent letters home, he became a lonely walker in the ruins.
During his escape, he gathered survivors with different personalities one after another: Lin Xiaoman, a girl who is proficient in mechanical maintenance, Lao Zhao, a retired doctor with medical knowledge, and Zhou Kai, who was a company executive but had no power. In a desperate situation with no water, no food, and surrounded by zombies, they must pass through the urban area known as the "Loop of Death" and reach the legendary "Ark" safety zone located on the outskirts of the city.
However, what is more terrifying than the walking corpses is the human heart. In the survivor strongholds along the way, some people betrayed their companions for resources, and some established authoritarian rules to enslave others. Zhang Bing not only has to lead his team in a desperate fight against the walking dead, but also has to make a choice in the gray area of human nature - stick to the bottom line of a soldier, or become like a monster in order to survive? When they finally arrived at the "Ark", they discovered that the so-called safe zone was just the beginning of another larger conspiracy.
