In Vladivostok, Far East Russia, South Korean National Intelligence Service Manager Zo is assigned to track an international crime syndicate operating near the border. His investigation intersects with Park Geon, a North Korean State Security official sent to investigate a recent security breach. The situation is complicated by Hwang Chi-seong, the North Korean consul general, whose personal interests conflict with the official mission. At the center of the intelligence gathering is Chae Seon-hwa, a worker at a North Korean restaurant. As the agents from both sides attempt to secure her as a human intelligence source, she is forced into a position of high risk.