The school year is over and all of Hogwarts is going home for the summer. Giving in to temptation, Malfoy, Crabbe and Goyle conspire to stall Harry, Ron and Hermioneâs departure and strand them alone in Hogwarts for the summer. But something goes wrong and all six of them get stranded with no hope of getting home. If that wasnât the worst of it, strange sounds have started coming from the Slytherin dorms a sense of utter dread has permeated the entire school. Together, facing unknown horrors and fighting a maddening urge to flee in terror, Harry and the other students must find out⦠Whatâs in House Slytherin?