Adolescence is and always will be a time of intense emotional confusion, especially if you spend it in a closed environment. That’s the case with Rebecca, a young girl haunted by her father’s suicide, who is a student at an exclusive female boarding school. She pours her heart out in a diary, much of it focused on Lucy, her beloved roommate. Their relationship changes drastically with the arrival of a mysterious new student, Ernessa. As Lucy abandons her for this new girl, Rebecca becomes consumed with thoughts of jealousy and suspicion — Ernessa is dangerous, evil, a vampire. Is there any truth to all this or is Rebecca slipping into insanity?