There are three brutal murders committed in London, New York and Sydney respectively. The three assassins, hired by White Tycoon, arrive at Hong Kong and methodically do away with their unsuspecting victims, unleashing their skills through various ingenious ways. The two gangs, the Scorpion and the Serpent, are played off one against the other. White Tycoon hopes to fulfil his dream of eliminating his rival and taking over their lucrative business. The mastermind behind the Scorpion is Phoenix and her right-hand man known as "Panther" while heading the Serpent is Hercules whose girl friend is Rose, who, having innocently become involved in the dealings of the Serpent, is killed by Panther. Alison, Rose's sister, befriends Phoenix and begins to work for the Scorpion, hoping to track down her sister's killer. Further conspiracy is Panther's own quest for personal power. Phoenix is led to believe that Alison is a double-crosser. Alison is thus sent on a dangerous mission to meet Hercules. There is a big fight. Meanwhile, Hercules' girl friend, Cherry, almost falls to victim to the assassins but incidentally saved by the Interpol Agent called Scot, who subsequently sets out to capture the three assassins while the police are given the task of rounding up the members of the Scorpion and the Serpent. Alison keeps her rendezvous with Hercules, who informs her that they have both been double-crossed. Alison has by this time figured out the identity of her sister's killer and thinks that Phoenix has tried to use her. The police arrive and in the ensuing battle Hercules is arrested while Alison escapes. At the villa, Alison threatens to kill Phoenix. The final confrontation takes place at the Big Dam between While Tycoon and Scot. A hard challenge follows by all means. The Mission Thunderbolt is carried on and on. (IFD Films and Arts Limited)
There are two versions of this movie : - the original version directed by Dung Gam Woo, - the new editing with new scenes shot by Godfrey Ho.