Harry Potter and the Chamber of Secrets
Harry Potter and the Chamber of Secrets is the second of seven books in the Harry Potter series authored by J. K. Rowling. Harry Potter and his friends Ron Weasley and Hermione Granger discover that someone called the "heir of Slytherin" is unleashing a monster to purge Hogwarts of all "mudbloods", a derogatory term for wizards with Muggle (non-wizard) parents. Most people think Harry is Slytherin's heir because he can talk to snakes, which is a rare ability and one that was possessed by Salazar Slytherin, one of the four co-founders of Hogwarts, along with Helga Hugglepuff, Rowena Ravenclaw, and Godric Gryffindor, which is why a serpent is the mascot of Slytherin House. Harry remembers that he was almost sorted into Slytherin by the Sorting Hat in his first year and it only put him in Gryffindor because he asked it to. Harry suspects that his enemy fellow student Draco Malfoy might be the heir of Slytherin but eventually discovers that it is the memory of the Dark Lord Voldemort's sixteen year old self who is Slytherin's heir.