A vulnerable student is filled with a sense of foreboding about a mysterious new arrival at a girls' boarding school in director Mary Hannon's adaptation of Rachel Klein's gothic novel. Helped to recovery by her best friend Lucy (Sarah Gadon) after the suicide of her father, sixteen-year-old Rebecca (Sarah Bolger) soon begins to feel ostracised when Lucy falls under the spell of darkly moody newcomer Ernessa (Lily Cole). When her concerns about the new student's motives are dismissed as jealousy by Lucy, a chance reading of a gothic novel triggers the belief in Rebecca that Ernessa may in fact be a vampire and is trying to steal her friend's life force. When staff and pupils at the school suddenly begin to suffer a series of deadly freak accidents, Rebecca decides to uncover the truth about Ernessa once and for all.