Violet enrolls at Elm Hollow, a private school for girls on the outskirts of a sleepy coastal town. For her, this is a chance to start again after a terrible accident, leaving her demons behind. A little strange and insecure, she desperately tries to become her own among classmates and soon finds herself invited to an advanced training group led by the charming and mysterious art teacher Annabel. The girls study not only the history of art, but also the mysterious past of the school, the founder of which was burned at the stake for witchcraft. The program includes Greek myths and Celtic legends, the history of witch trials and ancient rituals. And no matter how Annabel convinces her students that the classes are exclusively academic, they cannot resist practical experiments. Gradually, their actions become more and more gloomy and get out of control. How far will girls go to protect each other... or destroy each other?