The original cast of the passionate iron triangle returns after 5 years. Catholic priest Kim Hae-il (Kim Nam-gil), prosecutor Park Kyung-sun (Lee Ha-ni) and detective Gu Dae-young (Kim Sung-bun) join forces to fight against evil forces! A memorial service revealed the secrets of an underground drug trafficking group. Kim Hae-il decided to go to Busan with his partner, disguised as a seminary teacher, to start an investigation.