Rubeus Hagrid
The trio return to Hogwarts for the school year on the Hogwarts Express train, which is suddenly boarded by dementors, ghostly prison guards that are searching for Black. One enters the trio's compartment, causing Harry to pass out, but new Defence Against the Dark Arts teacher Remus Lupin repels the dementor with a Patronus Charm. At Hogwarts, headmaster Albus Dumbledore announces that dementors will be guarding the school until Black is captured. Hogwarts groundskeeper Rubeus Hagrid is announced as the new Care of Magical Creatures teacher; his first class goes badly when Draco Malfoy deliberately provokes the hippogriff Buckbeak, who then attacks him. Draco exaggerates his injury, and his father Lucius Malfoy later has Buckbeak sentenced to death.