Bo, Dong, and Pingchuan have been the best friends since middle school. Together they open a hot pot restaurant in one of the caves, which used to be a bomb shelter in Chongqing. They nostalgically name their hot pot restaurant ‘The Classmate Cave’ (TCC). Due to their mismanagement, TCC goes bankrupt and has to be sold in order to pay for the debt. Bo, Dong and Pingchuan then decide to dig into the cave further for bigger space and better selling price.

Unexpectedly, they discover a bank vault next store during their ‘restaurant expansion’.  Struggling between greed and moral rights, they have yet to decide taking the money for ‘better’ use. At this time, they realise Xiaohui, their old classmate who had a crash on Bo, works in the bank. It seems that the cave reunites the four classmates, yet the reunion is just the start of soon unforeseen chaos…