In 1983, South Korea sent an undercover military unit to North Korea on a top-secret mission. On their way home, the special agents were mercilessly killed as part of a cover up. Years later, the mission's sole survivor Jin-pyo and his adopted son Yoon-sung return to South Korea to exact revenge on the five men behind the betrayal. One by one, Yoon-sung exposes his targets' crimes and delivers them to the prosecutor. But Jin-pyo is out for blood, putting father and son at dangerous odds. Korean television action drama.