Inchon, Korea. Citizens run for cover in the pouring rain while the mysterious Sungmin (Ahn Sung-Ki) walks up Forty Steps and stabs another man to death. He disappears with a briefcase full of cash while his accomplices finish off the dead man's subordinate. The police investigation reveals an underground drug world at war. Detective Woo (Park Joong-Hoon) is the determined police detective who pursues the elusive Sungmin in a chase through the maze of the city streets and hideaways. Along the way, Woo and his men hunt down the nefarious figures of the drug world. They also find Jugo (Choi Ji-Woo), the woman who loves Sungmin. But Sungmin remains at large, a master of disguise and elusiveness, until the final spectacular showdown with detective Woo in the suburbs of a coal-mining town.