Severus Snape is the Potions master at Hogwarts in the Harry Potter series, and The Prisoner of Azkaban is the third film in that series, released in 2004. Snape's tense relationship with Harry Potter is central to the story, which is why short voice clips of the character are widely shared by fans. On soundboards and in video edits, this Azkaban-era clip is reused as shorthand for suspicion, discipline and dark Hogwarts atmosphere, keeping it popular long after the film's release.