Song Zheng, an ordinary college student, unexpectedly encountered a disaster from the sky. A huge mouth opened in the sky, alien beasts poured into the world, and the peaceful campus instantly turned into a purgatory. In a desperate situation, he was saved by Xiaobai, a snow-white alien beast, who risked his life. He accidentally concluded a symbiosis contract, sharing power and perception, and then embarked on the path of an alien beast contractor. Lin Wan, his former sweet best friend, betrayed due to jealousy, colluded with a mysterious organization to hunt him down and seize the core of the contract; strange survivors formed a team to travel together, but there was also a hidden danger. Song Zheng led Xiaobai from a deadly battle on campus to an abandoned industrial area, and fled from the temporary safety zone to the main safety zone. He used the power of the contract to kill ferocious beasts and break through the black-clad siege. In the blood and fire, he lost his cowardice and gradually grew into a strong man who could protect his companions. Alien beasts are rampant and people are unpredictable. There seems to be a bigger secret behind this disaster. Song Zheng can only stand side by side with Xiaobai, carving a way out in the ruins of the apocalypse, and igniting the fire of hope in the name of a contract!
