Kim Nam-Hee

Hyun, a loner high school student who lost his entire family in a terrible accident, is forced to leave his home and has to face a new reality where monsters are trying to wipe out all of humanity. Now he must fight against all odds to try and race against the clock to save what is left of the human race before it's too late.

The series tells the story of Yoon Hyun-woo (Song Joong-ki), a loyal higher-up employee working for chaebol Soonyang Group, who was betrayed and murdered by a member of the Soonyang family to cover up a tax evasion scheme. Hyun-woo later wakes up in 1987 discovering that he has been reincarnated into the body of Jin Do-jun, youngest grandson of the Soonyang family. Using these circumstances to his advantage, he starts his revenge by plotting a hostile takeover of Soonyang Group. - wikipedia

Kim Jung-ho quits being a prosecutor despite a promising future after discovering the dirty secrets of his prosecutor father. Kim Yu-ri is a strong-willed and righteous woman. (imdb)