Harry Potter and the Half-Blood Prince

The classroom door opened as she spoke, and Snape stepped into the corridor, his sallow face framed as ever by two curtains of greasy black hair. Silence fell over the queue immediately.

“Inside,” he said.

Harry looked around as they entered. Snape had imposed his personality upon the room already; it was gloomier than usual, as curtains had been drawn over the windows, and was lit by candlelight. New pictures adorned the walls, many of them showing people who appeared to be in pain, sporting grisly injuries or strangely contorted body parts. Nobody spoke as they settled down, looking around at the shadowy, gruesome pictures.

“I have not asked you to take out your books,” said Snape, closing the door and moving to face the class from behind his desk; Hermione hastily dropped her copy of Confronting the Faceless back into her bag and stowed it under her chair. “I wish to speak to you, and I want your fullest attention.”

His black eyes roved over their upturned faces, lingering for a fraction of a second longer on Harry’s than anyone else’s.

“You have had five teachers in this subject so far, I believe.”

You believe… like you haven’t watched them all come and go, hoping you’d be next, thought Harry scathingly.

“Naturally, these teachers will all have had their own methods and priorities. Given this confusion I am surprised so many of you scraped an O.W.L. in this subject. I shall be even more surprised if all of you manage to keep up with the N.E.W.T. work, which will be more advanced.”

Snape set off around the edge of the room, speaking now in a lower voice; the class craned their necks to keep him in view.

“The Dark Arts,” said Snape, “are many, varied, ever-changing, and eternal. Fighting them is like fighting a many-headed monster, which, each time a neck is severed, sprouts a head even fiercer and cleverer than before. You are fighting that which is unfixed, mutating, indestructible.”

Harry stared at Snape. It was surely one thing to respect the Dark Arts as a dangerous enemy, another to speak of them, as Snape was doing, with a loving caress in his voice?

“Your defenses,” said Snape, a little louder, “must therefore be as flexible and inventive as the arts you seek to undo. These pictures,” he indicated a few of them as he swept past—“give a fair representation of what happens to those who suffer, for instance, the Cruciatus Curse” (he waved a hand toward a witch who was clearly shrieking in agony) “feel the Dementor’s Kiss” (a wizard lying huddled and blank-eyed, slumped against a wall) “or provoke the aggression of the Inferius” (a bloody mass upon ground).

“Has an Inferius been seen, then?” said Parvati Patil in a high pitched voice. “Is it definite, is he using them?”

“The Dark Lord has used Inferi in the past,” said Snape, “which means you would be well-advised to assume he might use them again. Now…”

He set off again around the other side of the classroom toward his desk, and again, they watched him as he walked, his dark robes billowing behind him.

“…you are, I believe, complete novices in the use of non-verbal spells. What is the advantage of a non-verbal spell?”

Hermione’s hand shot into the air. Snape took his time looking around at everybody else, making sure he had no choice, before saying curtly, “Very well—Miss Granger?”

“Your adversary has no warning about what kind of magic you’re about to perform,” said Hermione, “which gives you a split-second advantage.”

“An answer copied almost word for word from The Standard Book of Spells, Grade Six,” said Snape dismissively (over in the corner, Malfoy sniggered), “but correct in essentials. Yes, those who progress in using magic without shouting incantations gain an element of surprise in their spell-casting. Not all wizards can do this, of course; it is a question of concentration and mind power which some”—his gaze lingered maliciously upon Harry once more—“lack.”

Harry knew Snape was thinking of their disastrous Occlumency lessons of the previous year. He refused to drop his gaze, but glowered at Snape until Snape looked away.

“You will now divide,” Snape went on, “into pairs. One partner will attempt to jinx the other without speaking. The other will attempt to repel the jinx in equal silence. Carry on.”