The four of them go to the mansion on the west mountain to arrest Wang Huai Gu. Wang Huai Gu tells them that a powerful man in black with black crape covering his face brought the first part of the Lantingji Xu to him and asked him to organize an appraisal convention to find the second half of the scroll. Wang Huai Gu was sure that the second part of the Lantingji Xu would have been long gone. So, he got greedy and wanted to keep the first half of the scroll to himself. (Source: Viu)