Professor Quirrell is the Defense Against the Dark Arts professor at Hogwarts. Stuttering and seemingly harmless, Quirrell appears as nervous and squirrelly as his name suggests for most of the story. It is he, for example, who nearly faints when announcing the news that a troll is loose in the school. However, by the end of the novel, Harry learns that Quirrell has merely put on an act of timidity; he is actually ambitious and manipulative, and working to bring Voldemort back to full power. For the majority of the novel, Harry, Ron, and Hermione suspect that Professor Snape (the cold and sneering Potions professor) is trying to get the Sorcerer’s Stone to Voldemort. However, at the end of the text, we learn that Professor Snape is actually a red herring—a character within a mystery narrative who is intended to be misleading or distracting. Professor Quirrell teaches Harry, and subsequently the reader, an important life lesson: things are not always as they appear. Professor Quirrell acted meek and anxious at all times, allowing Harry and his friends to overlook many key clues that could have led them to the correct conclusion. For example, Hermione accidentally knocks Professor Quirrell headfirst into the row in front of him while setting Professor Snape’s robes on fire during Harry’s first Quidditch match. She does so because she suspects that Professor Snape is jinxing Harry’s broom and she wants to startle him into breaking eye contact, which would subsequently break the connection. However, at the end of the text, we learn that the spell was actually lifted because she accidentally broke Professor Quirrell's connection. Additionally, it was Quirrell who let the troll into Hogwarts on Halloween. Through Harry’s misjudgment of Professor Quirrell, Rowling demonstrates that evil can take many forms. She also trains her readers to think critically when they are presented with mysteries in the books to come.