Yu Dahai's honest police team is forced to fabricate cases to keep their jobs. However, the police station's water pipe bursts, and they unexpectedly encounter Luo Siji, Luo Hao, and Niu Dalun, a gang of tomb raiders disguised as plumbers.
Four police officers open up a lobster restaurant as a cover in order to catch a notorious drug dealer, only to find their secret recipe is more popular than they expect. When they get caught up in their new business venture, they find a bigger conspiracy at work.