U.S. state department agent Elliot Cromwell is working with Interpol tracking Harry Pimm, a courier for the Asian crime syndicate known as Black Lion. When Pimm arrives from Hong Kong at Kennedy International Airport in New York City, members of a splinter Black Lion faction stage a shootout in the customs inspection area. Pimm escapes unharmed, but his assistant, Prescott Chang, is hit. Chang is taken to the hospital, but escapes. When Elliot Cromwell reports to Interpol, they tell him to find Pimm because he is the only person who knows the identity of the Black Lion leader, known as “The Founder.” Hong Kong policewoman Major Shan, who was working a case involving illegal fireworks, followed Pimm from Hong Kong. She is assigned to work with Cromwell, along with airport policewoman Sergeant Terry O’Shea, who witnessed the shootout. Cromwell, Shan, and O’Shea follow a lead to Harlem and then go to a warehouse on the Lower East Side where they find chemicals used for making explosives. They also find Prescott Chang’s dead body along with a videocassette from “The Founder,” who is shrouded in darkness, saying the internal warfare among the factions must end. Outside the warehouse, the three spot Angelica Bethencort, a high-priced prostitute who frequently travels with Harry Pimm. They follow Angelica, hoping she will lead them to him. Angelica boards a flight to London, England, and the three also make the trip. Upon arrival in London, Interpol relieves Cromwell of duty, upset that he recruited two female police officers to assist with the operation. Interpol places George Norris in charge of “Operation Fireworks” and Norris has Shan and O’Shea follow Angelica around town as she shops for expensive evening gowns. However, Norris is a double agent with instructions to kill Harry Pimm. At a fashion show, Elliot Cromwell tells Terry O’Shea he is unofficially still working the case and kisses her, but they are interrupted by Major Shan. George Norris spots Harry Pimm in the fashion show audience and tries to shoot him, but Cromwell stops him. Pimm fires a machine gun at Cromwell and Norris before escaping, and Angelica Bethencort is arrested. Backstage, Cromwell discovers a crate containing gold bars. He demonstrates how the bars were shaved into gold wire, which was sewn into dresses. They deduce that Angelica was taking the gold-laced garments to New York City, and using the proceeds to finance the Black Lion syndicate. Norris rigs Cromwell’s car to explode, but O’Shea warns the agent and saves his life. Cromwell, Shan, O’Shea, and Norris board a commercial jet bound for New York after getting a tip that Harry Pimm chartered a private plane to the city. During the flight, Cromwell radios Interpol and learns that Harry Pimm is an alias for Leo Kalb, twice convicted for arson. Cromwell also tells Interpol of his suspicions about George Norris being a double agent. After Interpol returns the case to Cromwell and reinstates his license to kill, Norris is arrested. Upon arrival in New York City, Cromwell, Shan, and O’Shea return to the Lower East Side warehouse where they find crates of fireworks, which conceal guns and other weaponry. Meanwhile, Harry Pimm and Black Lion operatives, led by a man named Haggard, arrive at the warehouse. After Pimm plays a videotaped message from “The Founder,” demanding absolute obedience, the operatives realize that Harry Pimm is “The Founder.” Pimm’s men shoot and kill Haggard and his men, then capture Elliot Cromwell. They are about to behead Cromwell with an ancient Asian sword, but he escapes with the help of Shan and O’Shea. However, the gunplay ignites the fireworks, causing them to explode. Cromwell escapes, but realizes O’Shea is still trapped in the warehouse and rescues her just before the building erupts into flames. Interpol congratulates Cromwell on a job well done. Cromwell and O’Shea thank Shan for her help and leave for a romantic evening.