After an explosive increase in world population and the depletion of world resources, the lifespan of all humans is now limited to 75 years. When Zhang Yi, a high school student known as the most evil existence in his school, tries to help his grandfather avoid the mandatory death, he discovers something by accident — the purpose of the mandatory death law is to cover up a secret that mankind cannot bear to know. From then on, all kinds of things and people that he has never heard of keep getting drawn into his life. The truth of the world is gradually revealing itself to him!