Once Taki is back in Hong Kong from Tokyo, the unit begins investigation on an addictive and harmful performance-enhancing drug named "Happiness". The emotionless leader of the police unit Sergeant Kayama ("Commander", Yuen Woo-ping) suspects that Happiness is imported from the Rapter World by a tycoon named Daishu ("Yuen", Tatsuya Nakadai). He orders Taki and Ken to slip into Daishu's mysterious 150th birthday party. There Taki meets his former lover ("Gaye", Michelle Reis), who is now a mistress of Daishu. On the other hand, Daishu and his raptor staffs are having a meeting, because they don't know who is importing Happiness the drug either. The staffs are nervous, but Daishu persuades them to control humans' economy to bargain with humans.