After his kidnapping, he tries to get into the gang business by offering to manage the finances of the legal parts of their operations. In the beginning, he is very firm that he will not touch any of their illegal dealings, he offers to be their financial advisor. Cui Dong Dong loves the idea, but Xia Luiyi is against it because he doesn’t want him anywhere near the dangers of being associated with the gang. Chu San even convinces Cui Dong Dong to invest in one of his money-making schemes.

Basically, this is how it starts and throughout the story he uses his financial knowledge to navigate his way within Luiyi’s gang and also deal with rival gangs and keeps getting deeply involved with everyone and everything in the process.