The Starting Point.

Crime ring leader Lee hires prostitute Seon to kill his subordinate Seok-gu who has threatened to take his place. Seon tempts Seok-gu to go to Mountain Seorak to assassinate him. But she falls in love with him in the journey and confesses everything to him. In fact, they have been shadowed by the spies Lee sent and bloody fight breaks out. Seok-gu in the end defeats all the villains.