In June 1998, the most wanted international fugitive Sik Hak smuggles from North Korea a large quantity of chemical poison into Hong Kong. Department of Security chief Ma Lap Hei hopes to use Sik Hak's comrade Dor Dut to save Hong Kong. Dor Dut due to head trauma loses his memory and forgets his father and son like relationship with Sik Hak. He even risks his life to report back to Ma. Both sides erupts into a fierce battle. Sik Hak suffers an injury while saving Dor Dut, who gradually regains his memory. Facing a ton of biochemical weapon, loyalty and moral conflict, making Dor Dut face the most severe test in his life......