Livid

Lucy Klavel starts her practical training as an at-home nurse under the stern guidance of Mrs. Catherine Wilson. She learns basic patient care and observes Wilson's strict methods. This early period establishes their mentor-mentee dynamic and hints at the hidden secrets of the mansion they will encounter.

During a visit to the ancient mansion, Wilson introduces Lucy to the bedridden Deborah Jessel and hints at a rumored treasure on the property. Jessel is presented as a once-renowned ballet teacher, now a fixture of the eerie estate. The treasure rumor plants a dangerous lure that will pull Lucy and her friends into the house's dark secrets.

Back at home, Lucy shares the treasure legend with her boyfriend William and he agrees to join, along with his brother Ben. The trio decides to search for the rumored gold and jewels on Halloween night. The plan transforms from a routine job into a perilous thrill-seeking expedition.

On Halloween night, Lucy, Will, and Ben crawl into the mansion through a window and descend into the basement. They are drawn to a room filled with stuffed animals and a lone locked door. The air is thick with dread as they realize the mansion is guarding its own dark history.

Lucy suspects that a key worn by Deborah Jessel unlocks the concealed door. Inside, a white sheet hides a mannequin-like corpse of a young girl named Anna, dressed in a ballerina outfit. When Lucy twists the pedestal key, the corpse spins to a haunting melody, revealing the room's sinister purpose.

The group attempts to flee upstairs, but the window they entered through is now secured by iron bars. The mansion seems to close in around them, cutting off obvious exits. They realize the building itself is a sentient menace guarding its secrets.

Ben wanders into a seemingly doorless operating room with no clear purpose or origin. Veiled ballerinas suddenly materialize and kill him, shattering the group’s fragile sense of safety. His death marks a swift descent into the mansion's supernatural danger.

Lucy encounters Mrs. Jessel seated at what used to be Anna's tea party table. A flashback reveals Jessel's brutal past as a ballet teacher who, along with her daughter Anna, was connected to bloodshed. The revelation confirms the Jessels are vampires and that the mansion hides a centuries-old danger.

Will is attacked by Ben, who now moves as a vampire. Will stabs Ben with scissors in an act of desperate defense, but Mrs. Jessel closes in and kills Will. The attack demonstrates the corrupting power of the mansion and its creatures.

Lucy learns that Anna is not dead and the two collide as Anna attempts to drink Lucy's blood. Lucy fights to push Anna away, barely managing to keep her safe. Mrs. Wilson arrives and uses sedation to subdue Lucy, complicating the struggle further.

Jessel performs a grim ritual, implanting moth pupae into the throats of Lucy and Anna to exchange their souls. The procedure is brutal and ritualistic, signaling a final attempt to control who inhabits which body. Both girls become pawns in a supernatural exchange that will decide their fates.

Anna wakes in Lucy's body, her eyes now altered in color to signify the swap. Jessel orders Anna to dance, but the altered body seems to resist, signaling a shift in power and the potential for rebellion. The body swap raises the stakes for the final confrontation.

Wilson tries to discipline Anna, but Anna stabs Wilson with scissors and then turns on Jessel. The mother-daughter alliance fractures as the sisters turn on one another. The mansion's evil unravels as blood spills on the floor.

Lucy (in Anna's body) and Anna (in Lucy's body) overpower Jessel and push her from a third-floor balcony. The shattering violence frees the remaining captives and marks the end of Jessel's reign. The two girls seize their escape from the mansion together.

Lucy and Anna walk along a seaside cliff after fleeing the mansion. Lucy, inhabiting Anna's body, leans over the edge and unexpectedly rises into the sky. Her scars vanish as she floats away, leaving Anna to watch the strange, otherworldly departure from shore.