The film was originally loosely based on a true incident in which a stone statue in a cemetery was lost while filming was going on. A few of the crew members with historical and archaeological background investigated and found the lost statue: not realizing its historical/cultural importance, it was accidentally removed by workers hired by the movie production company during the site arrangement and forgot to put it back where it was.
This mishap is the result of the local government trying to making quick bucks by allowing commercial activities on historical sites. To prevent such things from happening again, new laws were implemented.
This true story was actually the original plot of this movie, but thanks to the liberalization brought by the reform introduced in China, screen writers were able to alter the story to the current plot for suspense and the current plot was eventually adopted.