A renowned combat veteran, LT Choi Tae-in, is ordered by HQ to lead the mission as an act of redemption for his crime (For visiting an illegal brothel, which led to the death of his platoonmate at the hands of a female Vietcong). He is given seven days to lead a team of nine soldiers to find the missing men. HQ then recruits members for the mission by giving promises of an early discharge from the Army and a journey home on a full-fledged carrier airline upon success of the mission.
The men then set sail to the island referred to as R-Point from a dock and, upon arrival, took 2 photos of the expedition team. But, not long after proceeding into the jungle, they are ambushed by the Vietcong. They take cover and fire blindly, until LT Choi flanks the pillbox and disables it with a rocket launcher. When they investigate the pillbox, they found a female guerrilla next to the decomposing body of another VC. One of the soldiers searches her for intelligence items, looks at her bracelet with a cat bell tied to it and is tempted to take it. After being told that his fingers will rot off if he steals a dead person's belonging, he quickly relinquishes the idea. After arguing over who should finish the girl off, LT Choi eventually decides to leave her be and move on.
After a while they come across a grassy field with two large stones at the entrance with carvings; the first stone saying “Hundreds of years ago the Chinese killed the Vietnamese and dumped their bodies in the lake, it has since been filled in and a temple erected in memory of the Vietnamese” and the second stone saying “Wherever you go, I'll be there. All those with blood on their hand will not...”. The last part is not legible as it was chipped off over time. Being soldiers, they shrug it off as a hoax and decide to think nothing more of it. That night after the men set up camp, Corporal Joh reveals he is a mortician's son and that the area the bodies are buried in is not a suitable place neither for the living nor the dead, adding that only ghosts are drawn to the area.
When they wake up the following morning, they find they had slept right in front of an abandoned French Plantation. They proceed to search the house, clear all the rooms and set up base. Sergeant Jung and Sergeant Mah found a small footlocker with maps left by the previous French garrison and a broken tape-player, but laments the dilapidated state that it is in. After the briefing on the details of the mission, Sgt Mah realises that Sgt Oh was from Battalion 53 and would know how the missing men looked like. Sgt Oh denied this, after which LT Choi passes the order to search the surrounding area in two squads.
When on the search, Cpl Joh misses the main group because he was relieving himself. He looks around in despair and shouts out to his comrades to no avail. Eventually, he found the group of soldiers at a field up ahead. He whispers to the men, furious at them not answering his calls. The men show no emotions and do not react to Cpl Joh, who notices the last man wrote "Jang Sook, wait for me" on his helmet. He looks back at the forest, and turns around to see the soldiers going prone in the tall grass. Instinctively he does the same, but is confused when no one stands back up at the lack of hostilities. He stands, but does not see anyone in the grass.
1st Sgt Jin then notifies Lt Choi that Cpl Joh is missing. He leads his team and meets up with 1st Sgt Jin at the temple that the Chinese built. After a combined search effort, they finally find Cpl Joh hiding in a small opening. They chide Cpl Joh that evening back at the plantation and deride him for insisting that he saw soldiers, especially the man with the writings on his helmet. Sgt Oh is particularly irritated with this and warns Cpl Joh to stop his ridiculous rantings, and stops because they hear the approach of a helicopter in the distance. The men quickly rush outside to survey the situation and are surprised to see Americans this late into the night. Led by Sergeant First Class Beck, the U.S. Soldiers report that they are here to check on the batteries providing the plantation with electricity and adds that they only come here at night because the fog in the day presents a danger to flying. After the Americans finish with their business on the second floor, SFC Beck informs LT Choi of the history of the plantation as a French fort. He says that the French garrison here was wiped out in an instant by an unknown entity that was not the VC as the latter had yet to exist. Elaborating more, SFC Beck claims that nothing survives at R-Point. He is evidently amused at LT Choi's ignorance for not knowing about the rumours surrounding R-Point prior to their mission. Before leaving, he bets that LT Choi's men won't survive until the next maintenance trip four days later and reminds the LT not to touch the American's belongings on the second floor. But, as a gesture of good luck, the Americans leave a rack of beer for the Koreans before retreating into the night.
In the meantime, Sgt Oh confronts Cpl Joh at a quiet spot outside the plantation. He gets rough with the Corporal, and insists that the latter confess to how he came to know of the "Jang Sook" helmet. Cpl Joh repeats that he saw the guy with the helmet, much to the disbelief of Sgt Oh. Cpl Joh pushes the Sergeant aside, remarking that he has had enough from Sgt Oh.
Back at the plantation, Sgt Mah brings the tape-player to the radio operator, Cpl Byun. He asks Cpl Byun if he can fix it, and is reassured in return. Lt Choi came by, and Cpl Byun reports that the radio is receiving local transmissions only. He adds that he received a transmission from a French unit not far from the plantation, and that the French soldier told him that his name was Jacques. Jacques mentioned that he served in the same unit with his twin brother, Paul, and that his unit would be coming by the Koreans soon. Lt Choi counters by noting that Cpl Byun does not understand French, hence would not understand whatever the supposedly Frenchman was saying. This is then dismissed as a sign of severe fatigue.
The soldiers are resting at their bunks when Cpl Byun appears with the repaired tape-player. He plays it and the men are then dancing to the music from The Ventures. They make merry until the point where the music is replaced by a recording of the presumably last moments of the missing soldiers. The screams and gunshots from the player fills the room. Lt Choi then requisitions the player and replayed the tape over and over at his bunk.
On the night that Sgt Mah and Sgt Jung are assigned on guard duty, they spot Private Chung walking off into the forest. That exact night, Lt Choi hears ringing cat bells, and sees the VC girl who ambushed them at the beginning. Strangely, the girl was now wearing a white Áo dài and is walking around the plantation.
In the morning Cpl Lee, the machine-gunner, reported that Pvt Chung is missing. Cpl Joh and Sgt Park are searching the grounds when Sgt Park sits on the steps to rest. He tells Cpl Joh to go ahead without him and reassures the latter that he would keep his promise and hook him up with a hot chick when they return to Seoul. While the ever-vain Sgt Park checks his appearance with a mirror, a drip of blood falls on him. Park looks up in disgust, and had the living daylights scared out of him when a bucket-full of blood splashes on him. Lt Choi realises that the blood was from the body of Pvt Chung, hanging off the roof of the plantation. Choi decides to search the surroundings for the VC supposedly responsible for killing Chung.
At the temple, Choi finds incense burning at the altar. He realises that the VC must have been here to offer their respects to the dead. Hence, he has his men set up booby-traps around the temple to kill the VC when they return to light more incense. That night, while reporting back to HQ, Choi is derided by his superior for being delusional. He is told that Pvt Chung IS one of the missing men, and that he only 9 men to start with. The soldiers begin to recollect their memories on Chung, and can only remember him present with the group at the landing and not at the docks. They look at the photos they took to confirm their suspicions and find Pvt Chung amongst them. They suspect the supernatural, but are not convinced. Only Lt Choi knows the truth.
Sgt Oh recollects his memories and thinks back to his platoonmate with the "Jang Sook" helmet. He remembers that his comrade handed him a camera to pass on to Jang Sook, but Sgt Oh presumably kept the camera for himself after hearing that his friend went missing at R-Point.
Lt Choi, contemplating the situation, notices the same VC girl outside the plantation. This time, he follows the girl and inadvertently arrives at a graveyard where the French soldiers were buried. He looks at the crosses over the grave and is shocked to see one marked "Jacques et Paul" (French for Jacques and Paul). He thinks back to the transmission that Cpl Byun told him about and is thoroughly convinced that R-Point is haunted. When he returns to the base, the soldiers hear a booby-trap going off. They rush to the temple to find Sgt Oh lying in a pool of blood. Evidently, Oh tripped off one of the traps. He is disillusioned and keep repeating "I'm sorry...", finally reaching out to Cpl Joh and asking the latter for forgiveness.
After this incident, 1st Sgt Jin told Lt Choi that he would lead a group of men to search for the missing parties. The next morning, they set off in two squads. Both sides were unable to maintain radio contact with the other during the search, hence 1st Sgt Jin had his men hunker down at a clearing and try getting through to Lt Choi. Instead of staying with his men, he ventures out into the wilderness alone and falls through a valley. Sgt Park, unable to find 1st Sgt Jin, assumes command of the squad and sets off to meet up with Lt Choi. Lt Choi, in the meantime, arrived at the crashsite of a UH-1 Huey helicopter. He finds the body of Sergeant First Class Beck, instantly recognisable by the Peace necklace that was on him. Sgt Mah and Sgt Jung, who were the only ones willing to follow Lt Choi, were frightened beyond their wits. They decide to meet up with Park before proceeding with any other searches.
Jin, who woke up in a gully, explores the caves within. He hears the transmission that was sent to the HQ at the beginning, and moves in to investigate. He comes up to a small hole in the cave walls and sees a soldier, back facing him, with a radio. The transmission continues until he turns the operator around to see a decomposing body.
While walking to meet up with Choi, Cpl Joh finds himself the target of a ghost. He tells Cpl Lee, and is told to shoot anything that moves. He sees the illusion of Sgt Oh walking ahead and fires his M16. Incidentally, the direction he fired in was where Choi was coming from. In the confusion, Sgt Mah is shot and subsequently dies.
The men arrive at the base, and Lt Choi breaks into the room containing the equipment that the Americans brought. Instead of finding the batteries, they find rusting and out-of-service radios. Obviously, the room was left to disuse for a long period of time, which then led Lt Choi to realise that the Americans were also dead and were ghosts. The men begin to panic, and Cpl Lee aims his MG at Choi. Choi nonchalantly pushes the MG away and slaps Lee to his senses, while the men pack the radio to the bunks for repair.
Cpl Byun, after repairing the radio, tries to contact HQ. His efforts, being in vain, adds to the tension. The radio then suddenly bursts to life and Lt Choi requests immediate evacuation. HQ confirms that a chopper will arrive at 5:50 am to pick the men up. After the transmission, there are sounds outside the plantation. The soldiers take up defensive positions, only to see 1st Sgt Jin come back with the head of the decomposed operator and the radio. Cpl Lee breaks down, runs to him and begs him to keep him alive. Jin, after asking him if that was what he wanted, grabbed Lee by the head and decapitates him. Choi guns him down, is fully aware that the ghost is manipulating the soldiers into killing each other. Eventually Cpl Byun breaks down too, and blinds Sgt Jung with a grenade. Sgt Park then drops to the floor and laments why he has to suffer like this, and Cpl Joh shoots him in the head. After Choi guns Joh down, he tends to Jung's injuries. While bandaging Jung, he saw a photo in the left breast pocket on Jung. He takes it out; it is a photo of the French Garrison. He looks at the faces and finds a familiar one amongst the Frenchmen - the VC girl. At that instant, he hears more footsteps and then comes face-to-face with the VC girl. He tries, in vain, to bring his machete to bear upon the girl. Thus, not wanting to be possessed and then kill Jung, he orders Jung to aim his rifle in his direction and fire. Choi was killed at the last moment, leaving Jung to call out to him in despair.
Jung, driven insane, mumbles nonsense until the morning. He keeps insisting that all this is a prank played on him by the rest of the squad and keeps calling their names. The rescue team comes and the movie ends with the rescue chopper contacting HQ, reporting that they found one survivor, Jung, and that there were no signs of the rest.