A Russian organized crime group is set out to steal an advanced chemical weapon from Korea and two secret agents are out to stop them. Soo-ji is a veteran agent who is a master of all forms of martial arts and envied by her comrades. Jae-joon is a rookie who is never been out on the field and always goofs up on the job. The two agents don't know each other's secret identity. All that they know is that they hate each other, because they were once in a passionate relationship until Jae-joon, completely distraught over Soo-Ji's frequent absences and even harder to believe excuses, decided to break up with her. Now, tree years later and still oblivious about each other secret identity, the former lovers meet again and, as they try to work out their screwy relationship, keep going behind each other's backs in order to stop the Russian mob from acquiring a weapon of mass destruction.