Plot

A troubled teen named Kit Gordy is forced to join the exclusive Blackwood Boarding School, just to find herself trapped by dark forces around its mysterious headmistress, Madame Duret.

Since her father's death when she was a child, Kit Gordy has grown into a troubled teen to the disgust of her mother Ginny and her stepfather Dave Dabrowski, Called to the principal's office of her high school and accused of a failed attempt to burn it, she is expelled, but Dr. Heather Sinclair, member of the staff of the Blackwood Boarding School, appears to offer her a place in the next school year. Ginny enlists Kit against her will in an attempt to reform her daughter, and Kit travel to Blackwood, an isolated, dark old mansion in the middle of a forest outside the city. There she meets her companions: nice Izzy, shy Ashley, reluctant Sierra, and borderline Veronica, teens as troubled as herself. During dinner, Kit and the others meet Blackwood's headmistress, Madame Duret, and the rest of the staff: Professor Farley (math); Jules Duret (music); Heather Sinclair (arts); and Mrs. Olonsky, Madame Duret's rude right-hand peacekeeper. Locked in a place without Internet, cell phones, or any other trace of modern technology, Kit watches as everyone changes in strange ways: Izzy develops an extreme obsession for mathematics, Sierra for painting, Ashley for writing, and herself for piano; meanwhile, Veronica seems immune to obsession. Trapped between strange memory gaps and her love interest in Madame Duret's son Jules, Kit asks Veronica's to discover the reason for their different changes. They investigate the forbidden, ruined wing of Blackwood and discover that all of them--Izzy, Ashley, Sierra, Veronica, and Kit--have one secret in common, and that previous students suffered a horrible fate caused by Blackwood's supernatural forces, and it will be their fate as well unless they find a way to avoid it.—Chockys

Outcast troubled teenager Katherine "Kit" Gordy is invited to study in Blackwood and her mother and stepfather drive her to the old and isolated manor. She is welcomed by the headmistress Madame Duret with four other colleagues and forced to develop their talents in mathematics and arts. Soon Kit realizes that supernatural forces are possessing them and increasing their talents.—Claudio Carvalho, Rio de Janeiro, Brazil

Having a long history of disciplinary charges and suspensions for misconduct, fiery-tempered teenager Kit is running out of options. And forced by her parents to join the exclusive Blackwood Boarding School to improve her behaviour, troubled Kit arrives at the creepy old manor run by the institution's peculiar headmistress, Madame Duret. But as Kit and the school's only four other students find themselves abandoned at the gloomy mansion, soon enough, the girls begin to exhibit extraordinary talents they never knew they possessed. Does the young ladies' newfound aptitude for art, literature, music, and mathematics have something to do with Blackwood's sinister, spine-chilling secret?—Nick Riganas

Ginny Gordy-Dabrowski and her second husband Dave Dabrowski send Ginny's troubled teen daughter Katherine 'Kit' Gordy to Blackwood Boarding School. Odd headmistress Madame Duret and stern housekeeper Miss Olonsky greet Kit upon her arrival. Kit notices an ominous door at the end of a dark hallway, which Madame Duret identifies as being off limits.

Fellow troublesome teens Ashley, Izzy, Sierra, and Veronica, who soon begins having regular run-ins with Kit, arrive at the school. Madame Duret confiscates everyone's cellphones as she explains that although her rules are harsh, she aims to ensure each hand-selected student realizes her full potential. Miss Olonsky begins administering nightly medication to each girl.

The girls meet mathematics teacher Professor Farley, literature instructor Dr. Heather Sinclair, and music teacher Jules, who is also Madame Duret's attractive son. Madame Duret doubles as the school's art instructor. As the girls go about their daily studies, Ashley quickly becomes an impressive poet, Sierra becomes extraordinarily adept at art, and Izzy excels at math.

Kit begins exhibiting exceptional skill on the piano. During a private lesson, Kit confides in Jules about her father and the trauma she has suffered since his death when she was a child. Kit has a strange experience where she blacks out while outdoors and abruptly reappears inside in the music study.

Ashley startles the other girls when she has a vision of a woman named Elizabeth, whom she claims is the person who brings her the words that she writes. Kit sees a shadowy figure of a man in the hallway outside Ashley's room, prompting all of the girls to sleep together that night. Kit speaks about her father again while the other girls ponder why they were chosen for Blackwood.

The next day, Kit tells Madame Duret what she and the other girls saw. Madame Duret passes off the visions as a side effect of their pills, which she says they will no longer be given.

All of the girls except for Veronica continue excelling in their respective disciplines. Madame Duret chides her son after interrupting a romantic moment between Jules and Kit.

Kit notices that Sierra's artwork includes the initials T.C. just like several paintings in Madame Duret's study. Ashley claims she feels as though someone takes over her body when she writes. After doing research in the school's library, Kit concludes that dead painter Thomas Cole inexplicably possesses Sierra while poet Elizabeth Webb possesses Ashley and composer William Kessler possesses Kit when she plays piano.

Kit experiences a vision of flying bats crashing through a window. Kit also runs from several ghostly figures, which Veronica sees too.

Kit and Veronica decide to investigate the room at the end of the dark hall. Inside, they find files revealing that numerous other girls previously experienced similar possessions before being driven to suicide. Madame Duret and Miss Olonsky capture Veronica while Kit flees.

Kit experiences a vision of the building violently shaking. Afterward, Kit becomes drawn toward a vision of ghosts assembled around William Kessler at a piano. With Madame Duret and the Blackwood instructors encouraging her, Kit takes over for Kessler. A bright light envelops the chamber as Kit plays.

A disfigured ghost demanding that his music be played shakes Kit from her vision. Kit finds herself in the music study with Jules and demands to know what is happening.

Kit summons all of the students and teachers to the main foyer. Madame Duret explains that the girls have the gift of being vessels by which they can channel geniuses who died too young and thus complete their work. Madame Duret promises that Kit can connect with her father if she chooses to continue.

Kit finds Ashley trying to slit her wrists. Ashley later jumps from her window and dies after crashing through the greenhouse's glass roof.

Jules helps Kit by giving her keys to unlock the cabinet containing the confiscated cellphones. Kit calls 911.

Kit finds Sierra dead. Kit also finds Izzy entranced by a mathematical equation and tries snapping her back to reality.

Kit confronts Madame Duret and her instructors to tell them she called the police. Madame Duret expresses anger that Jules betrayed her for Kit. Miss Olonsky captures Kit.

Miss Olonsky locks Kit in a room where Kit finds Veronica demonically possessed and chained inside a circle of candles. As ghosts assemble around them, Kit encourages Veronica to fight against her possession. Veronica regains her own mind and is freed, but a candle gets knocked over in the process.

Izzy unlocks the door for Kit and Veronica as the building begins going up in flames. Still entranced, Izzy insists on staying behind and is shown standing near the staircase with flames around her, surveying the room.

Kit and Veronica find Miss Olonsky preparing to kill Jules when Dr. Sinclair unexpectedly knocks Miss Olonsky to the ground. Dr. Sinclair remains behind and becomes overwhelmed by ghosts as Kit and Veronica flee with Jules.

Ghosts confront Madame Duret. Madame Duret inadvertently stabs Professor Farley as the ghosts swarm her.

Miss Olonsky recovers and sees a vision of her dead son Michael, which is what she wanted when she agreed to work for Madame Duret. Miss Olonsky follows the ghost to the greenhouse where she dies in a sudden explosion.

Kit follows a vision of her father that ultimately leads Veronica safely outside. Kit and Jules remain in the foyer where they see flames consume Madame Duret. Jules sacrifices himself to save Kit from a falling beam.

Kit collapses outside as police and paramedics arrive and the building becomes completely engulfed. Kit's mom rides with Kit in an ambulance. While unconscious, Kit gets closure with her father's ghost in a final encounter before returning to life.