Episode 3 of Jirisan drops us back into the cliffhanger that episode 2 left us with. After finding the yellow ribbons, Yi-gang hears Dae-jin approaching and drops the bunch of files the ribbons were hidden under in her panic. She’s able to right everything before he arrives and he goes to his desk none the wiser, putting down a pair of eerily familiar black gloves.
On the mountain, the bushes rustle around Da-won as the blood-soaked person appears. She doesn’t seem to see the person, and heads back when Gu-yeong calls out to her. When she reaches the station, she lets Yi-gang know that she installed an automated sensor camera above the rock arrangement as per Yi-gang’s request.
Somewhere on the mountain a monk rings a large bell. A hiker tells his companions that there are apparently 28 worlds on top of ours, and the sound of the bell opens the ghost world. A woman joins them and tells them about the ghost of a blood-soaked man that people have spotted recently. According to her, everyone who spots him dies.
The ghost in question is elsewhere on the mountain and has a vision of an empty yogurt bottle floating down a river and a man seizing while foaming at the mouth. The ghost makes its way to Mang-bawi Rock and finds Da-won’s rock arrangement. Its face is finally revealed and we’re left staring at Hyun-Jo. He recognises the arrangement as a signal from Yi-gang and moves one of the sticks to a new position.
We go back to 2018 where a prickly Yi-gang, along with a peppy Hyun-jo, receive a radio message asking for assistance on the Baektogol Valley restricted trail where illegal shamanism is occurring. The message causes Hyun-jo to have a flashback in which he is on the mountain clad in military uniform.
The pair arrive at Baektogol and are joined by Gu-yeong and Il-hae. Sol also arrives to observe the shamanism in action. The rangers, very chaotically, start breaking up the gathering. As the commotion dies down, Hyun-jo approaches a little girl who was with the group. She delivers to him a prophecy that he is destined to roam the mountain even after death. In the stream she kneels before is a strange talisman that even Sol has not encountered before.
Sol tells Hyun-jo that the Korean expression “go to a valley” (meaning “to die”) originated in Baektogol Valley, which has strong yin energy and has been host to a long list of horrific events. The valley is littered with crosses and stone pagodas to mark the many people who died there without graves.
That night, the rangers go out to drink so that ghosts don’t stay attached to them. Sol, ever the spiritual enthusiast, parts with the group so as not to chase any ghosts away. As they drink, Il-hae reveals that Hyun-jo was in the top of his cohort for the ranger test but volunteered to come to Mount Jiri (which is usually avoided for its rough terrain). He’s the opposite of Yi-gang, who was the lowest and apparently hated the mountain.
Yi-gang drinks a whole bowl of sweet potato makgeolli, which makes Gu-yeong and Il-hae nervous. She takes off with Hyun-jo in tow. Hyun-jo wants to know why she became a ranger if she hated the mountain, which makes her launch into a drunken rant about her relationship with the mountain at each age beginning at age six.
The following day on the mountain an old woman sets out food offerings at a cluster of stone pagodas along with an old picture of herself with her mother. Overcome with emotion, she lies down at the base of a tree covered in bullet holes and falls asleep.
Back at the station, Hyun-jo reads over a ruck march request. The document mentions Baektogol, which causes him to have a vision of the valley at night while someone falls and an empty yogurt bottle is dropped. Before Yi-gang can question him, the phone rings with a request to check on the old woman, Granny Geum-rye, who isn’t answering her phone.
We cut to Granny Geum-rye, still asleep. Someone wearing black gloves places a second yogurt bottle next to the one she already had among her offerings.
As they head out, Yi-gang explains to Hyun-jo that Granny Geum-rye lost her mother as a young girl at Baektogol and goes up the mountain many times a year in commemoration. The pair arrive after nightfall at the spot where Granny Geum-rye had been resting. The food offerings, bar the two bottles of yogurt, are there, but Granny Geum-rye is nowhere to be found. Hyun-jo asks about the bullet riddled tree and Yi-gang explains that there was a civilian massacre a long time ago.
Since they’re in a reception area, Yi-gang tries calling Granny Geum-rye to no avail. Hyun-jo wants to search Baektogol because of his vision but Yi-gang is openly cynical. He’s about to go alone, heading in the wrong direction, when Yi-gang relents and shows him the way.
At Baektogol, Hyun-jo finds the specific spot from his vision, but Granny Geum-rye is absent. A group of soldiers come upon the pair, their leader, Lieutenant Choi, recognising Hyun-jo and addressing him as “Captain Kang”.
Lieutenant Choi asks Hyun-jo if he was discharged because of an incident that happened in this very place. Hyun-jo changes the topic to Granny Geum-rye. One of the soldiers, Private Ahn, recounts how he saw a person fiddling with a pink backpack when he fell behind earlier in the day. In a flashback, it’s obvious the person is our gloved culprit. Yi-gang pulls up a picture of Granny Geum-rye in a pink backpack and Private Ahn identifies it as the same one.
As the soldiers settle down for the night, Private Ahn carefully sips from a yogurt bottle he conceals in his sleeping bag.
Yi-gang and Hyun-jo find the backpack where the soldiers said it would be. Inside is a bag of Common Rustgill, an extremely poisonous mushroom that can kill if ingested in large enough amounts.
Meanwhile, Granny Geum-rye stumbles and falls. When she looks up the scene before her is a fiery landscape. A line of people wearing hanboks are gunned down. Among them are her younger self and her mother. Granny Geum-rye covers her ears to block out the guns and doesn’t hear Yi-gang’s incoming call.
Fortunately, Yi-gang and Hyun-jo hear the ringing and follow the sound. Granny Geum-rye is approached by the apparition of her mother and takes her hand. When the pair reach her she has passed away. Hyun-jo administers CPR in vain while Yi-gang has a mild panic attack.
While they wait for assistance, Hyun-jo tells Yi-gang that a sergeant died under his watch at Baektogol among the stone pagodas. A flashback shows us Hyun-jo leading his men in a ruck march on the mountain. One of the men, Kim Hyun-su, is limping behind the rest. When they stop for a break, Hyun-jo is made aware that Hyun-su hasn’t been seen for about 30 minutes. They search for Hyun-su, and we realise this is the same flashback Hyun-jo had earlier. Hyun-jo finds Hyun-su splayed on the ground by the pagodas, already dead, and he falls after smashing into a pagoda while scrambling to reach Hyun-su.
Hyun-jo tells Yi-gang his visions began after that night, and he’s come to view them as a gift. A call from Lieutenant Choi interrupts them. Private Ahn is missing, and they need help.
Hyun-jo and Yi-gang make their way back to Baektogol where Hyun-jo steps on an empty yogurt bottle like the one from his vision. The soldiers find them. According to one, Private Ahn fell ill and went away to vomit but never returned. They found traces of his vomit at the entrance to a nearby forest but couldn’t search the forest without becoming lost themselves. Yi-gang explains that it’s a climax forest full of similar-looking trees. After receiving instructions from her on how to avoid direction illusion, they renew their search.
A spooked Private Ahn runs through the forest, ending up at the edge of a cliff. The gloved man observes with a smile as Private Ahn is about to fall, but Hyun-jo grabs him at the last moment. Private Ahn begins to seize and foam at the mouth, and from his perspective the forest is red, and the gloved man watches him. In reality, soldiers stream through the trees and call for a medic helicopter.
Sometime later, Yi-gang accompanies her grieving grandma to Granny Geum-rye’s funeral. Outside, Gu-yeong tells Hyun-jo how Yi-gang found the bodies of her parents herself.
Hyun-jo goes to see Yi-gang later that night about his visit to a recovering Private Ahn. In a flashback, Hyun-jo calls Private Ahn out on the lie he’s been telling about drinking bad river water. Private Ahn admits that he received yogurt from the gloved man by Granny Geum-rye’s backpack.
Hyun-jo rehashes his earlier vision, which also showed someone collapsing after having the yogurt, but at Baektogol instead of the forest. Yi-gang still doubts him, especially after his vision didn’t lead them to Granny Geum-rye.
On another day, Hyun-jo returns to the pagodas at Baektogol and realises that his vision was of Hyun-su’s last moments, and strangely, someone has rebuilt the pagoda he smashed into that night. He comes to the conclusion that Hyun-su was murdered by someone who has continued to kill people on the mountain.