Han Jin Woo gets involved with unexpected case and he returns to the medical examiner office after 4 years.

Elite doctors chase a mysterious death and attempts to solve the mystery related to rare diseases.

The old-timer Bae Tae Shik butt heads with Han Jin Woo acting as the genius medical examiner. The two always differ in opinion, but whenever a case needs to be solved they respect each other's strengths and act as an unbeatable duo.

Han Jin Woo and his team of medical experts continue to solve mysterious deaths and cases larger in scale and more intractable than before, including the truth of a rare disease that had been hidden behind seemingly simple crimes.