Eighteen-year-old temporary worker Chen Fan is bullied brutally by a foreman. After accidentally swallowing an ant, he awakens the Beast Evolution System.
To raise money for the father of his childhood friend Jiang Xiaoyu’s medical surgery, Chen Fan makes a living by underground boxing matches. He stumbles upon a shocking secret: Xie Zhiran is running illegal genetic human experiments inside the factory, with Liu Qiang and the boxing gym boss acting as his pawns.
Gifted with the superpowers of various wild animals, Chen Fan teams up with allies to destroy the experimental base and defeat the genetically modified villains. Most of his beast abilities fade away after the final battle. In the end, he and Jiang Xiaoyu return to an ordinary peaceful life.
