The ruler of Tang Dynasty is afraid that the foreign tribes may one day attack his empire. Therefore he intructs the governor-general of Kansu province, FOK CHING WAI to re-construct the Yuk Mon Gate. WAI is a man who always talks big. In order to speed up the progress, he believes he should kill boys and girls to makes stacks. HUNG TIN YAU is sent to supervise the work. When he and his family reach there, he witnesses the collapse of walls. Many workers are buried and he rushes to save WU YAN, disregarding his own safety. WU YAN thanks him a lot.

YAU and his family take temporary accommodation in WAI's house. SU CHUK's beauty attracts WAI. A filthy idea germinates in WAI's mind.

TIN YAU has to work round the clock as the deadline is approaching while it is threatened by sand storms.

WU YAN is aware of WAI's filthy idea and he tells YAU……