The same thing happens to Snape, the grand final twist, that shatters all previous perceptions of his character, and replaces them with a devastating better version of the man Harry says was the bravest of them all. On screen, we marvel as Alan Rickman shifts from villain to hero, mastering both of them with equal talent and intensity. Forget page-three-hundred-and-ninety-four – the speech of Severus Snape, headmaster of Hogwarts, is said with such careful malice in every single word, that you’ll start to wonder who’s the real villain of the story. And when he finally shows his true self, when all is revealed, there’s a kind of emotional impact that, perhaps, you never expected from this saga. A feeling that crushes you even more when the camera turns to Harry.