Ryu Deok-hwan plays the role of Han Jin-woo, a special forensic doctor of Korea University. According to the plot, Han Jin-woo will live a secluded life in the mountains near Gyeonggi Province after the end of the fourth season. In this series, the cases seem to be perfect natural death at first glance. Or died in an accident, but only forensic doctor Han Zhenyu can find clues from the mysterious murder case, pull through the layers of fog, and find the truth of the case.