Mount Jiri will revolve around the activities of the park rangers, including going on rescue missions and protecting the ecosystem against the backdrop of Jiri Mountain, one of KoreaŌĆÖs most famous mountains. Previously, Jun Ji Hyun (Seo Yi Kang) and Ju Ji Hoon (Kang Hyun Jo) decided to take on the lead roles, making headlines. On top of that, Sung Dong Il and Oh Jung Se also confirmed their roles, raising the expectations. Oh Jung Se, who showed exceptional performance in the recently-ended ItŌĆÖs Okay to Not Be Okay, will play Jung Gu Young. He is an extremely practical ranger with the motto of ŌĆ£I need to live first in order to save others.ŌĆØ He never works overtime and keeps his vacation and monthly leave like a clockwork. Sung Dong Il plays Jo Dae Jin, the branch manager of Jirisan National Park Haedong Branch. He has spent more than half of his life as a ranger and is nicknamed ŌĆ£Mout Jiri Man.ŌĆØ Jo Dae Jin has a strong sense of duty and honesty as a ranger and always feel responsible for his junior rangers. Meanwhile, Mount Jiri is written by Kim Eun Hee, best known for NetflixŌĆÖs Kingdom series and drama Signal, and is directed by Lee Eung Bok, who worked on Descendants of the Sun, Mr. Sunshine, and Goblin. Source (1)