Hong Kong police officer Zhu Fulong (played by Donnie Yen) was demoted due to a work mistake. When he was helpless, his fiancée Ke Er (played by Zhou Liqi) broke off the marriage. The double blow of career and love made him unable to recover. After six months of overeating, his weight soared to 220 pounds! His boss, Officer Huang, couldn't bear his continued degeneration, so he appointed Zhu Fulong to Japan to escort a prisoner and promised to restore his position as long as he completed the task. Unfortunately, when he came to Japan, unfortunate events happened to him one after another. Not only did he lose all his property, but even the prisoner escaped during the escort. Fortunately, he got the help of former Hong Kong police officer Xiao Sao Ge (played by Wang Jing) to temporarily get out of trouble. In order to complete the task and retrieve the prisoner, Zhu Fulong and Xiao Sao Ge acted together. Unexpectedly, in the process of finding the truth, they discovered the shocking conspiracy of the Japanese gang...