The Potions professor at Hogwarts, and a longtime member of the Order of the Phoenix. Cold and enigmatic, Snape is still nursing his resentment for being bullied by James Potter during his time at Hogwarts, which he expresses by treating Harry with malice and cruelty. His conduct, as well as the knowledge that he once belonged to Voldemort’s Death Eaters, causes Harry to loathe the professor and suspect him of aiding the Dark wizard. However, he’s unable to shake Dumbledore’s trust in him; in remaining loyal to Snape, the headmaster shows Harry his faith in the possibility of personal transformation and redemption. At the end of the novel, Snape kills Dumbledore and appears to help the Death Eaters who have infiltrated Hogwarts. This shocking act seems to confirm Harry’s belief that those who have once been evil can’t change their ways; however, it also foregrounds one of the most important revelations of Deathly Hallows.