iQiyi Original K-series Jirisan, starring Gianna Jun and Ju Ji-hoon, and created by director Lee Eung-bok (Descendants of The Sun, Guardian: The Lonely and Great God) and writer Kim Eun-hee (Signal, Kingdom), presents its latest character posters. In the posters, Gianna Jun and Ju Ji-hoon are clad in their National Park Ranger gear and the focus is on their expressions of worry paired with taglines that hint at mysteries with far-reaching consequences.

Park rangers Gianna Jun and Ju Ji-hoon will together unravel the untold mysteries and dangers of the peak. In Jun’s poster, she is seen in a fire-fighting jacket with a respirator mask hanging from her ear, concerned about what has happened on Jirisan. The poster’s tagline translates as “Someone’s sending a signal from that mountain,” bringing questions as to who that might be. Ju Ji-hoon’s poster sees his pained expression paired with the tagline, “I’m sure that person’s alive,” leaving fans wondering who the survivor may be and how he came to know of the person’s condition.

In addition to the stellar cast and crew line-up, Jirisan’s production studio Astory also surprised fans by announcing that Jin, star of Korean idol group BTS is set to sing the series’ main theme OST. Astory shared, “The main theme song enables Jin to express his unique voice quality and fans can expect to enjoy it from midway through Jirisan. A release date for the song will be announced at a later time.” The amazing collaboration of talents will leave fans around the world waiting with bated breath for the series debut.

Jirisan follows the team of national park rangers who are responsible for search and rescue on Jirisan. Experienced ranger (played by Gianna Jun) and rookie ranger (played by Ju Ji-hoon) are set to unravel the secrets of the peak. The iQiyi Original K-series will exclusively simulcast with Korea on October 23rd on iQiyi International app or iQ.com worldwide.