In 1907, Dr. Paul Eswai is dispatched to the quiet village of Karmingam to perform an autopsy on Irena Hollander, a woman who died under mysterious circumstances in an abandoned church. Monica Schufftan, a medical student who has just returned to visit her parents' graves, is assigned as his witness. During the autopsy, they uncover a silver coin embedded in Hollander's heart, a macabre detail that hints at forces beyond a simple medical event.
The locals cling to old medicinal practices and superstitions, claiming that Karmingam is haunted by the ghost of a young girl who curses those she visits. After Nadienne, the innkeeper's daughter, is visited by the spectral child, Ruth, the village witch, performs a ritual to reverse the curse.
That evening, Eswai goes to meet his colleague, Insp. Kruger, at the villa of Baroness Graps. The Baroness says she knows nothing of such a Kruger. As he departs, the ghostly girl reappears, echoing the village's unease and hinting at a deeper history behind the deaths and the whispers that haunt the town.
Monica experiences a nightmare about the child and awakes to find a doll at the foot of her bed. She crosses paths with Eswai in the street, and he offers to drive her to the inn so she can sleep. At the inn, Eswai discovers that Nadienne is wearing a leech vine around her body as part of Ruth's treatment, and he removes the vine despite concerns from Nadienne's family.
In the local cemetery, Eswai finds two gravediggers burying Kruger, who has been shot in the head. Simultaneously, Nadienne is awakened by the girl at her window, who compels her to impale herself with a candelabra, a chilling moment that deepens the sense of danger surrounding the villagers.
Karl, the burgomaster, informs them that the ghostly girl is Melissa Graps, the dead daughter of the Baroness, and that she is responsible for Hollander's and Kruger's deaths; he also reveals that Monica’s adoptive parents—the Schufftans—were not her real parents. When Karl goes to retrieve evidence proving so, Melissa compels him to destroy the documents and to take his own life, a cruel twist that pushes the investigation toward a revelation of hidden family ties.
Turned away by Nadienne's father due to her death, Monica and Eswai attempt to draw the villagers' attention by ringing the church bell. Inside the church, they discover a secret passageway, and Monica experiences a striking sense of déjà vu as they uncover a Graps family tomb, which includes that of Melissa Graps, who died in 1887 at the age of seven.
They find a staircase leading out of the tomb, which takes them into Villa Graps, where the Baroness confronts them in the hallway. She reveals that Melissa was trampled to death while fetching a ball during a drunken festival. Melissa's ghost appears, and Monica suddenly vanishes through a doorway. Eswai chases after her through a looping sequence of doorways, confronting a doppelgänger of himself, and ends up locked in a room before being spirited out of the villa. He regains consciousness at Ruth's home, where Ruth explains that the coins found in the hearts of the victims were placed there by her as talismans to ward off the Baroness’s supernatural powers. Ruth reveals that the Baroness has invoked Melissa's ghost to punish the villagers and that she intends to kill the Baroness to avenge Karl, who was her lover.
Back in the villa, the Baroness reveals to Monica that she is her mother, and Melissa is her elder sister; after Melissa's death, the Schufftans had sent Monica away to be raised in Gräfenberg for protection. Melissa's ghost reappears, chasing Monica down the staircase into the tomb, and urging her to throw herself from a nearby balcony. Ruth arrives to confront the Baroness, who stabs Ruth through the chest with a fire poker. Ruth, however, manages to strangle the Baroness to death before dying herself, thereby laying Melissa's troubled soul to rest. Eswai arrives just in time to save Monica, and together they leave Villa Graps as the sun rises on a new day, the village's mysteries finally beginning to fade into the light.
