Chin Wong Sing is Kim Chow Ling's uncle and he dressed up as the Moon Monster to scare Kim away so he could get his fortune. After faking his own turn into a statue, he proceeded to chase Shaggy Rogers and Scooby-Doo, who had arrived with the gang due to their van's flat tire.
He planned to scare Kim into tossing the treasure into the bay, and Fred Jones advised him to do so. Kim did and a current carried the sack with the treasure to a secret cave. Here Chin retrieved the fortune, but was soon after captured by Mystery Inc.