The 8th Night

A monster crosses from hell to the human realm 2,500 years ago. Buddha removes the Red Eye and the Black Eye from the creature and seals them inside Śarīra caskets. The Eyes are buried across the world—the cliffs of the Far East and the desert of the Far West—and Buddha commands his followers never to meet them.

In the present day, Professor Kim Joon-Cheol travels the desert to prove the existence of the Śarīra caskets. He finds a relic he believes is one of the caskets, but the scientific community brands his discovery fraudulent and shuns him. His obsession to prove the find grows.

Fourteen years later, Kim opens the casket and pours six vials of blood into it, along with his own. The Red Eye emerges, seemingly possessing him and reshaping his quest toward reuniting the Eyes. The boundary between reality and nightmare starts to blur as the demon awakens.

In Gwangju, Bhante Ha-jung, custodian of the Black Eye casket, senses the Red Eye has awakened. He tells Cheongseok the legend of the two Eyes and that, to prevent their reunion, they must kill at least the seventh pillar—the Virgin Shaman. Cheongseok is tasked with finding Bhante Seon-hwa for help.

The following morning, Bhante Ha-jung is found dead, sitting upright with the Śarīra casket by his side. Cheongseok resolves to pursue Seon-hwa and continue Ha-jung's mission to stop the demon's plan.

In Chilgok, the Red Eye possesses a hunter and drives him to a secluded motel to attack a couple. The victims are found shriveled with holes in their skulls, and detectives Kim Ho-Tae and Dong-jin investigate the supernatural pattern. The case hints at a force beyond ordinary crime.

The Red Eye moves from the motel victim to a delivery man encountered in a tunnel near a meditation group. The pattern of possession expands to more people connected to the same circle, deepening the mystery for the police.

Cheongseok leaves Gwangju in search of Seon-hwa, losing his bag along the way. He locates Seon-hwa, who is now a construction worker and a silent monk. Through flashbacks, Ha-jung's spirit reveals Seon-hwa abandoned the monastery to avoid succession, leaving behind restless spirits clinging to him.

Cheongseok discovers the sixth pillar—the Red Eye on a young woman in white—at the Virgin Shaman's house. Seon-hwa mistakenly suspects the seventh pillar is this young woman and declares his intent to kill her, while Cheongseok tries to intervene.

Detective Dong-jin explains that the victims trace back to Kim Joon-Cheol's meditation group and the blood rituals. He reveals the Virgin Shaman is alive—Ae-ran, a ghost saved by Professor Kim—and shows Kim a talisman crafted from his own blood.

Seon-hwa and Cheongseok execute a trap to force the Red Eye to possess Dong-jin. Ae-ran's manipulations escalate, turning the pursuit into a deadly confrontation where Dong-jin is fatally affected. The plan crescendos toward the revelation of the seventh pillar.

In the final confrontation, Cheongseok is briefly possessed by the Red Eye, but Seon-hwa sacrifices himself to stop the demon from reuniting the Eyes. Cheongseok kills Seon-hwa and succeeds in preventing the reunion. He returns the Śarīra casket to its origin at the India-Pakistan border, where Ae-ran appears; the chains on her ankles fall away, suggesting she is freed.