A notorious burglar Ken has arrived in HK and targets on a valuable diamond necklace. It is the last job Ken plans on completing before he flees the country with this girlfriend, Yu-fung. Ting and Chong are invited to join a special unit, which is led by Bo Bo, to track down the ringleader. After Ken successfully gets hold of the diamond necklace, the conflict over the booty allotment soon develops into a fierce fight among the gang members. Ken is trapped by Yuen, another gang leader of the same camp. In an attempt to rescue Ken, Yu-fung turns to join hands with police to catch Yuen and the other gang members.