Author's Notes:

The title of this chapter is taken from Ron’s dialogue at the beginning of chapter eighteen, “Birthday Surprises,” of J. K. Rowling’s Harry Potter and the Half-Blood Prince (page 350 in the 2005 UK hardcover edition). This chapter covers a great deal of canon time (the events of chapters seventeen through twenty-seven of HBP, or, roughly, January through June) and makes reference to numerous canon events that occur during this time period. If, by some bizarre quirk of fate, the timeline of HBP is not etched upon your brain and you find yourself in a muddle, the Harry Potter Lexicon provides quick synopses of each chapter and an overall timeline for the book.

Cheers, as ever, to Vaughn for her beta services, especially in the face of RL surprises! All errors are my own, and feedback is always welcome.

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Insidious

by Grainne

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Chapter Thirteen: The Little Potions Prince


Monday morning, Snape was startled from his hasty class preparation by a lone knock on his office door.

“Come in,” he said irritably.

Much to Snape’s surprise, Draco Malfoy sauntered in—much to Snape’s surprise, that is, because 1) Snape had grown accustomed to the young man ignoring their appointments and 2) Snape had been so distracted by the flower diary he hadn’t actually remembered the appointment himself.

“You asked to see me, sir?” Draco crossed his arms over his chest and leaned against the open door.

Snape studied Draco for a moment. The young man's tone and posture were decidedly casual (a pale imitation of the father’s languid arrogance), and Snape could tell that he was trying to keep his expression neutral. However, the dark circles under his eyes and the blue veins visible beneath the pale, drawn skin told another story. Draco’s holidays had not been particularly restful, nor, Snape would wager, merry.

“When I tell you to come in, you come all the way in,” Snape said. “And close the door behind you.” There was a brief flicker of some emotion in the grey eyes—Snape could not tell if it was fear or anger—and then Draco did as he was told.

Snape shut the Defence Against the Dark Arts textbook he’d been reviewing, placed it to one side, and folded his hands on the desk. He waited, watching Draco to see if he would betray any further emotion. Draco picked a spot just above Snape’s right shoulder and stared vacantly, his lips pressed together in a stubborn bow.

“I hear you have a new house guest,” Snape said at last. “How is your mother coping?”

Draco looked at him for a brief moment, seemingly surprised, before his gaze slid away again.

“I have no idea what you are talking about, sir.”

“Come, come, Draco—don’t lie to me.” Snape placed one hand flat on his desk and leaned forward in his chair. “I know for a fact that a mutual friend of ours has been placed at Malfoy Manor.”

“As I said, sir, I know nothing about it.” The young man’s tone was bored now, but Snape noted that he had a mighty grip on the strap of his school bag. “But even if I did, I’m sure he wouldn’t want me to discuss it here at school, with you.”

Snape bit back the curse that rose to his lips. “I thought you might come to see reason over the holidays,” he said. “I can see that I was mistaken.”

“If you say so, sir.”

Snape rose from his chair in a single, swift motion and stalked around the front of his desk. Draco flinched but, to his credit, did not retreat.

“Do not take that tone with me, Draco,” Snape said sharply. “I swore to your mother that I would protect you, and I will do so, despite your aunt’s irritating paranoia regarding my intentions. What I will not do is tolerate your insolence. Is that clear?”

A fleck of spittle landed on Draco’s cheek. He wiped it away slowly with the back of his hand and then, still staring into the distance, he nodded.

“What was that?” Snape said, cocking his head and cupping a hand around one ear.

“Yes, sir,” Draco said sulkily.

Snape nodded his approval. He was debating whether or not to dismiss Draco for now and try again later when the young man added, “Aunt Bellatrix and I missed you on Boxing Day, sir.”

Snape blinked. Then his eyes narrowed, and he took a step closer.

“I would have thought,” Draco went on, “that we would have seen you, you being such a good friend of the family and all, you being such a particular friend of my mother.”

Snape mentally counted to ten, his hands twitching at his sides. It really was inconvenient that the giving of good, solid thrashings did not fit most people’s (and certainly not Narcissa Malfoy’s) definition of “watch over and protect from harm.”

“And I would think,” Snape said at last, his voice low and dangerous, “that you, being such a devoted son, would start thinking very carefully about just what you are trying to accomplish—what you are really trying to accomplish—and about who truly shares your agenda.” Snape took another step toward Draco. He restrained himself from reaching out and shaking him, forcing the young man to look him in the eye.

“For instance, if you wish to, say, guarantee your mother’s safety and your father’s release from Azkaban, your Aunt Bellatrix might not be the best person to turn to for advice. Dear Bellatrix is a fount of wisdom on many subjects—in fact, I hesitate to say a word against her—but you may find that her ultimate goal in life is rather…well, different from your own. Unless, of course, you also—and oh, won’t Miss Parkinson be crushed!—harbour an unrequited physical passion for our master? Hmm? Is there something you’d like to tell me, Draco?”

Snape raised his eyebrows suggestively. Draco’s eyes grew wide, and then he lowered his head, his fingers plucking nervously at his bag strap.

“May I be excused, sir? I really don’t want to be late for class. As you said before Christmas, all this acting business is vital, and where would you be without it?”

“Get out,” Snape said coldly. If the boy would not listen…if the boy was determined to meet his every attempt at aid with insolence or disinterest… But before Draco reached the door, something compelled Snape to try one more time.

“Draco,” he said, his tone gentle now, “your mother trusts me. Let that be enough, for now. Let me help you.”

Draco turned around, shaking his head muzzily as if coming out of a bewildering dream (or nightmare). His eyes met Snape’s at last, and what Snape saw there caused him great sorrow.

“With all due respect, sir, I don’t think you can.”

And then Draco was opening the door, was slipping out into the corridor, was…gone.

*******

For the next few weeks Snape spent every free moment he had—or rather, a good portion of the time he normally reserved for making rounds or sleeping—in the Haven with Mrs Evans’ flower diary and the potion. There was something driving him now, some sense of urgency or great need. He did not care to examine it too closely; all he knew was that he wanted to have the potion squared away as soon as possible so he could focus his attentions on keeping this new recalcitrant, world-weary Draco from digging his own grave (and likely Snape’s along with it).

At first he merely added his memories of receiving the gift and reading Mrs Dursley’s note. When this failed to turn the potion completely clear, he focused his attention on Mrs Evans’ favourite plants, or at least on those plants that were associated, in her diary, with memories of her two daughters. He raided his own storage cupboard, “borrowed” a few things from Professor Sprout’s private greenhouse, and patiently stirred in the whole lot, one petal (or root or stem or seed or leaf) at a time.

These efforts worked to a degree—the potion grew lighter in colour and thicker in texture—but none produced the crystal clear, treacle-like substance described in the ancient scrolls.

Desperate, Snape turned his mind inside out searching for memories that would add to the bonds he was trying to create. He soon noticed that there was a pattern to his interactions with members of the Evans bloodline, and he also noticed that said interactions involved a great deal of deceit and selfishness and rash behaviour on his part. That could no longer be helped, however, and so he parsed the memories as best he could (or else qualified them with fresh thoughts) and stirred them into the mixture. He added more of his own blood. He even added, on a (admittedly ghastly) whim, the sweat wrung from one of Potter’s socks.

At last, feeling a bit silly, Snape hit on the idea of reading bits of the flower diary aloud. He started with a passage, written not long after Lily’s birth, about an entire field full of snowdrops growing wild. The family had been travelling by train to visit relatives, and Mrs Evans, catching sight of the spectacle, had exclaimed, “I’ve never seen so many all in one place! How many do you think there are?” and her husband had replied softly, “As many as we left in North Africa,” and this had so struck the young mother that she’d copied down the exchange, as well as written a lengthy commentary on war and her determination that her own flowers, her darling daughters, would never be counted in such a way.

Even Snape, with all his experience at repressing sentiment, had to exert a fair amount of effort to keep his voice steady as he read the passage.

The potion, however, remained unaffected. And although the string of expletives Snape let out turned the air in the Haven quite blue, the potion itself remained stubbornly pink.

Whilst glaring into the basin, Snape had the sudden idea to add the memory of his reading. He put his wand to his temple and focused on the feel of the diary in his hands, the sound of his own voice, and the rush of uncomfortable emotion Mrs Evans’ words had caused.

As soon as the silvery strand of memory touched the substance in the basin, Snape saw an immediate change. The potion grew lighter in colour; its consistency, which had been that of lumpy cake batter (oh, he remembered cake batter; he’d helped make cakes once. “Stop stabbing at it, Severus. Run the spoon around the outside of the bowl, gently, like, this.”) became that of thick, creamy custard.

Night after night Snape repeated this procedure with various passages from the diary—a description of Lily’s fascination with all the varieties of foxglove she encountered during a trip to the Lakes, a whimsical comparison of the two girls with their botanical namesakes, accounts of the small plots in the back garden that were allotted to Lily and Petunia as soon as they were able to wield spades—and each new memory clarified the potion further.

By February, the snow on the grounds had largely melted and Snape could see through the mixture to the bottom of the basin. With a fevered look in his eye (a look not unlike the one found in the eyes of many of his teenaged charges as St. Valentine’s Day approached), Snape said the final incantation and siphoned the contents of the basin into a large glass beaker. He inspected it by candlelight for any cloudiness or streaking (both highly undesirable, according to the scrolls). Satisfied that all was as it should be, Snape heated the beaker over a gentle blue flame until the mixture grew thin and lively once more. The final product went into a sturdy jar. Snape sealed this with a ground glass stopper (reinforced by a gob of wax and a handful of charms), and shrank it until it could be concealed comfortably in the palm of his hand.

As he didn’t know where or when he might have the opportunity to complete the ritual, Snape had decided that the best thing would be to carry the potion on his person at all times. He’d often travelled with concealed potions whilst in the Dark Lord’s employ, and he had long ago obtained a small leather satchel that he could wear beneath his robes without attracting much attention. The interior of the satchel was divided into compartments so that its contents wouldn’t knock into one another, and the leather had been charmed to contain and neutralise any accidental spillage.

Snape slid the shrunken jar into one of the satchel’s compartments. He sheathed the silver ritual dagger, shrank it as well, and placed it in the second compartment. Snape looked at the remaining compartments calculatingly before closing the satchel. He would add some emergency supplies—some Blood-Replenishing Potion, Draught of Living Death, poison…perhaps even some Polyjuice, just in case he needed a quick disguise.

Snape threaded the satchel onto its strap, and, baring the minimum of skin to the chilly sub-dungeon air, affixed the satchel in place beneath his robes, near his waist. It made a small bulge, but with the addition of a cloak or teaching robes, it would be undetectable to all save those in possession of Secrecy Sensors or wandering hands. Fortunately, as a member of the Order, Snape was exempt from being subjected to the former, and (fortunately or unfortunately) he was not likely to encounter the latter, either.

Snape reluctantly Banished the scrolls and other texts according to Dumbledore’s instructions. Snape longed to keep the Cognatus Libroviscera, that slim flesh-bound octavo of ancient blood and family magic that he’d inherited from his mother (he didn’t care how dangerous it was; it was now one of the very few things left from the wizarding side of his family), but he’d promised the headmaster that he would hand it over when he was finished with it.

“For safekeeping,” Dumbledore had said. When Snape had expressed concern that the headmaster might actually destroy it, Dumbledore had replied enigmatically, “No, Severus, that is not my right. But it is true that I am not eager to see it on the shelves in the library here at Hogwarts. It will be sent somewhere where it is not likely to be found. As we agreed.”

If Snape was reluctant to part with his mother’s book, he had no trouble bidding goodbye and good riddance to Ragnella, the hag in the portrait that guarded the Haven’s door.

“You are a foul, loud-mouthed, bloodthirsty crone,” he told her as he made his final exit. “I thank you for your dubious cooperation over the past several months and look forward to never seeing you again.” Then he wrapped his cloak about him and set off down the corridor.

“Children are for eating, not for teaching!” she screeched after him, sounding uncannily like the portrait of Mrs Black at number twelve, Grimmauld Place. “Filthy dough-eater! Child-minder! Ale-drinker! Creature of the light!”

“Now, you flatter me,” Snape shot back, but the hag, well stuck into her tirade, did not hear him.

*******

Snape was nearly back to his own quarters and was gleefully contemplating a bit of rest (at last!) when he heard a high-pitched cackling, followed by a sort of song.

“Sluggy’s little Potions prince,
that wee potty prodigy,
used his rod to stir the mince;
now his todger’s awfully…spottigy.”

Peeves came sailing through the door of an unused classroom, his mouth open wide. He stopped when he saw Snape, hovering in midair. He crammed his hands in his mouth, seemingly to stop a fit of giggles, but it didn’t work.

“I thought we had an agreement,” Snape said dryly. “No name calling and I keep the Bloody Baron out of your affairs and my nastier spells to myself.”

Peeves stopped giggling. He un-stuffed his fingers from his mouth and floated nearer, wiping his fingers on his stripy waistcoat.

“Is the Slithery Head looking to renegotiate?”

“No, I’m looking for an explanation as to why you’re suddenly so eager to have your tongue stuck to the roof of your mouth and your toes inserted up your arse.”

“But I’m not!” Peeves exclaimed, shooting up toward the ceiling in agitation.

“Then why are you calling me names?” Snape said, adding a long-suffering sigh. He’d never much liked the poltergeist (his sense of humour being rather too like some of the boys Snape had known in grammar school), but when he’d taken the post he’d negotiated a truce after coming to the realisation that having Peeves trailing about after him chanting, “Snivelly has dirty knees and cries for his mum going, ‘Wee! Wee! Wee!’” and recounting his worst humiliations from his school days would hardly help him—a young half-blood “war refugee”—cut an authoritative figure with the older Slytherin students.

“Call you names? Never!” Peeves glided down, smiling nervously.

“I heard you, just now,” Snape said angrily.

“What? Ohhhhhh.” Peeves grinned. “You mean, ‘Sluggy’s Little Potions Prince’?”

“Yes, that.”

Peeves cackled. “But that isn’t about you, sir,” he said sweetly, clasping his hands behind his back. “I’ve no idea what you get up to with your rod.”

“That’s it—I’m summoning the Baron.”

“All right! All right!” Peeves stuck his tongue out at Snape and then settled himself on a nearby bust. “Sluggy’s little Potions prince is what King Weasley called wee potty Potter one morning at breakfast,” Peeves said. “Peevsie has been calling him that ever since, as it annoys him and his bushy, pushy friend so much.” Peeves grinned nastily. “I’m planning a second verse, even, but first…you wouldn’t happen to have a good rhyme for ‘prodigy,’ would you, Snivelly?”

Without another word, Snape stalked off down the corridor, leaving Peeves to come up with his own dirty rhymes. He yanked open the door to his quarters and slammed it behind him. Sluggy’s little Potions prince, King Weasley—what are they playing at? Snape wondered as he paced his bedroom.

It was probably just some silly boyish nonsense—for all he knew those egotistical brats ran around calling one another Lord this and Lady that all the time—but still, why did it have to be “Potions prince”? That was his…

Snape sat heavily on his bed, his mind spinning away at a furious pace.

No, he thought. Where could he possibly...?

He leaped up and searched his bookshelves. He squatted and looked under all of the furniture. He rummaged through his trunk. He even tried a localised Summoning Charm, but nothing happened.

A moment later he was back out in the corridor, tearing toward the Potions classroom.

Inside the classroom he paused to catch his breath, then he tried the Summoning Charm again. The door to a corner cupboard rattled a bit on its hinges, but otherwise nothing happened. Snape stalked over to the cupboard and yanked the door open.

“Lumos!”

Snape stood up and whirled about, wand raised, as a bright light shone in his eyes.

“Severus! What on earth are you—”

“I could ask you the same thing, Professor Slughorn,” Snape said, sheathing his wand.

Slughorn lowered his own wand, sending its light into the nearest wall sconce with a little flick of his wrist. “Why, of all the ridiculous—this is my classroom, Severus; I have an Intruder Alarm Charm on it, of course. It woke me."

Snape coloured, mentally kicking himself for not thinking to check.

"From the most delicious dream, too. Golden syrup, buckets of it, all over—but I digress.” Slughorn giggled. “At any rate, please, call me Horace. We’re both teachers now, Severus; wouldn’t do to stand on—but what are you doing here so late? I thought you were one of the students, come to pilfer potions again. This time of year they always come after the Amortentia.”

“Horace,” Snape said stiffly, “you mentioned at your Christmas party that Harry Potter showed some proficiency at Potions.”

Slughorn nodded warily.

“And he has continued to do so this term?”

Slughorn nodded again. Snape gestured for him to elaborate, and the round man sighed. He waved his wand toward one of the desks, transforming it into a large overstuffed armchair. “Might as well be comfortable,” he murmured, sinking into it.

Snape remained standing.

“You heard how he got round Golpalott’s Third Law, surely?”

Snape shook his head.

“Really? I could have sworn it was all over the staff room.” Slughorn rubbed his hands eagerly.

Snape remembered that the man had never been able to resist holding court, had always relished being the purveyor of gossip, the teller of tales.

“A bezoar, can you believe it?”

No, Snape couldn’t. Potter hadn’t known what one was in his first year, and Snape doubted the idiot boy had lost any sleep remedying the situation since.

“The others had been slaving away over their cauldrons all class period,” Slughorn went on. “Harry brewed up some mess as well—just to fool me, I wager—but at the end of class he stood there as cool as you please and held out his hand. And what was in it?”

“A bezoar,” Snape said between clenched teeth.

“Sheer bloody cheek! Just like his mother—remember?”

And yes, Snape did, but he wasn’t about to share his reminiscences of Lily Evans just now.

“The two of you were quite a team there for a while, as I recall. I always wondered why—”

“And did Potter receive full marks for this ‘cheek’?” Snape cut in.

“What could I do, Severus? It was inspired!” Slughorn spread his hands and shrugged. “Although, mind you, I warned him not to try such a thing again, and I dare say his friends weren’t too happy with him—especially Miss Granger. You should have seen the look she gave him. One of the Furies was out a job that day, no doubt…very spirited girl, Miss Granger.” Slughorn chuckled, and a faraway look came into his eye.

Snape felt his pulse quicken. Granger was the only one from Potter’s year whom Snape would credit with remembering the discussion of bezoars, and if she was furious at Potter over the stunt, then she couldn’t possibly have been in on it. Besides, she never would have had the imagination, not to mention the sheer guts, to offer up a bezoar in response to the Golpalott’s Third Law assignment; she always did everything by the book.

…by the book.

Snape knew then that he was not mad, that his instincts had been true.

“Horace, Potter was not properly prepared to take Potions this year, am I correct?”

“Hmm?” Slughorn roused himself from his reverie—and Snape dearly hoped it wasn’t about Miss Granger, spirited or otherwise—and peered up. “Oh, quite the opposite, in fact. As I said, Severus, credit must go to you for—”

“I mean,” Snape interrupted, “that he was not expecting to take the course. He did not know that you would be teaching Potions? That you had agreed to take him on?”

“Ah, I see,” Slughorn said. “No. Evidently Dumbledore never told him which subject I was teaching. He and the Weasley boy were added to my class list last minute.”

“And what did they do for equipment and texts?” Snape prompted.

“They borrowed,” Slughorn said, sounding a bit puzzled by the turn the conversation was taking.

“From this cupboard?” Snape asked, pointing.

“Yes, yes,” Slughorn said, his eyes bulging as Snape flung the door open, bent down, and began rummaging inside.

There were many books inside, but only a handful of copies of Borage’s famous work. Snape quickly riffled through each copy—all were unmarked. One looked as if its owner had used it for Quidditch (and worse) but had never actually cracked the pages open.

“Er, Severus?”

“He’s got it,” Snape said over his shoulder. “The dirty little thief!”

“Severus! What’s got into you? No one has stolen anything. I was under the impression that everything in there was school property, but at any rate, they returned the books as soon as they received their own copies.”

Snape stood up abruptly, whirling to face the now visibly agitated man in the armchair. “What did you say?”

“I said that they returned the books they borrowed as soon as they procured their own copies—new copies—from Flourish and Blotts.”

Snape pinched the bridge of his nose. “And you…you’re certain they returned the borrowed items?”

“Yes!” Slughorn exclaimed, somewhat impatiently. “As a matter of fact, they returned them to me in person—two worse-for-wear copies of Advanced Potion-Making. I did as any rational person would; I chucked them back in that cupboard and promptly thought no more on the matter.”

“And there was nothing unusual about them?”

“No! Now really, Severus, I must insist that you either explain what’s got you so exercised or let me get back to my rooms. I’m an old man; I can’t take such excitement without the proper sustenance.”

“Nothing,” Snape muttered. “Good night, Horace. Sorry to have disturbed your disturbing fantasies.” And as Slughorn sputtered and struggled to rise from his armchair, Snape strode out of the classroom, no less vexed than he had been when he’d entered it.

He made for Dumbledore’s office, seething, and it was a very brave Hestia Jones who revealed herself and calmly announced that Dumbledore was away, but was expected back sometime before morning.

Right then, Snape thought. He’d been sneaking on and off the grounds of Hogwarts long enough now to know where the all the best Apparition spots were—the spots hidden from view of even the most prying eyes, yet not so deep into the Forbidden Forest that one had to cover any great distance before reaching the safety of the castle.

He marched out into the dark, damp, chilly night and began to make the rounds. The headmaster was bound to turn up sooner or later, and when he did, Snape would tell him that the whole thing was off. He didn’t know quite how Potter had managed it (he must have fooled Slughorn somehow, handed in another old copy of the book and hidden Snape’s copy), but several things were plain: Potter was a thief; Potter was a cheat; and Snape didn’t care if the boy had enough raw power to topple an entire army of Dark Lords—he, Snape, wanted nothing more to do with him.

He would write a letter to Petunia Dursley announcing that he was moving to Siberia to research steppe grasses, flush the potion down the loo, and patch any gaping holes left in his soul with liberal applications of firewhisky. Then he would wait and watch and do his best to fulfil his stupid vow to Narcissa. And then…

Well, it all depended, really.

But as Snape paced the forest, waiting for the telltale pop of Apparition, he managed to come up with several plans that all involved having nothing more whatsoever to do with Evanses and Dursleys and Potters, the fate of the wizarding world be damned.

Let Potter hate him. Let Potter try and kill him and go storming off to challenge the Dark Lord, wholly unprepared. Snape would not put himself out for the boy any longer. Dumbledore could find another way. There was still plenty of time.

*******


It was a chastened Snape who made his way back to the castle later that night in the headmaster’s wake. And it was an even more chastened Snape who stood in Dumbledore’s office in March, a week after Ronald Weasley’s poisoning and only a few hours after Potter had been sent to the hospital wing with his head split open.

The headmaster had stepped out for a moment. Snape began to prowl around the office, waiting for his return. Most of the portraits were either having a kip or away in their other frames, but Phineas Nigellus was wide awake and seemingly keen on conversation. He kept clearing his throat and waggling his eyebrows in an annoying fashion. Snape ignored him; Phineas Nigellus rarely had anything helpful to say.

He went over to Fawkes instead, who was looking poorly. The bird’s eyes were dull, and his feathers stuck out at odd angles. Snape, imagining that he might well look the same were he a bird, stroked the creature’s head in sympathy. But, of course, Fawkes was not just any bird. Fawkes would shortly burn and be reborn anew…

“Psst!”

Snape started and looked round. Phineas was glaring at him and beckoning him with one finger. Snape scowled and turned away, but the portrait was insistent.

“Psst! Psssst!”

“What do you want?” Snape said, stepping nearer the portrait.

“The boy knows,” Phineas whispered.

Snape sighed. “Which boy knows what, Phineas?” He had a feeling he knew, of course, but he thought he’d best make certain.

“The rude bespectacled one who is always in here. Severus, he knows about the vow you made to my great-great-granddaughter. He overheard you talking with my great-great-great—”

“With Draco,” Snape interrupted.

“Yes,” Phineas said snippily.

“And?”

“And nothing! I simply thought you’d like to know. Dumbledore tried to reassure the boy, after his fashion—you know, vague, but firm—but I don’t think the little blighter was entirely convinced. You’d best watch your back.”

“Thank you, Phineas, but I am well aware of Potter’s suspicions about me.”

“You knew?”

“Dumbledore mentioned it, yes.”

“His obsession grows—already it distracts him from our lessons together. I am worried, Severus. His soul must remain intact for as long as possible, of that I am becoming more and more certain every day. If he must kill, it must be only Voldemort. If he gives himself over to vengeance before that time…no, it must not happen. You will make sure that it does not happen.”

“But, Headmaster, he—”

“No, Severus! No more excuses. He is all of sixteen and you are more than twice that; you are also his teacher and one of his protectors. I wish you would…I wish you could…”

“Go easy on the boy, Albus? Ignore his blatant disrespect for his education, not to mention my person? Invite him round for tea and a sympathetic chat? I've only to look at him before I feel a migraine coming on, and if he ever manages to master nonverbals I'm sure he'll happily hex me to within an inch of my life next time my back is turned. It will never work.”

“…forgive yourself, Severus."

"Oh."

"Now, enough. You agreed to do it and that is that. I have other matters we need to discuss."

“It’s shocking,” Phineas went on. “In my day such insolence toward a teacher would have been severely punished. And we never would have entrusted such vital affairs to mere whelps. I tried to tell Dumbledore that he was a fool to—”

But at that moment Dumbledore returned, and Phineas Nigellus promptly shut his mouth and closed his eyes, pretending to be asleep.

“He thinks I am a fool to trust Harry,” Dumbledore said, easing himself into his chair, “and Harry thinks I am a fool to trust you. Twice a fool, and at my age, too! Well, Severus, have you come to make it thrice?”

Snape swallowed. “I’ve come to report that, as near as we can tell, McLaggen was not bribed, nor was his mind tampered with in any way. It appears that he is naturally reckless, hot-headed, and violent; Potter’s injury is indeed the result of an accident.”

“Ah.”

“The poisoning of Mister Weasley, however—”

Dumbledore held up a hand to silence Snape.

“Yes, I know, Severus. We’ve been over that. Have you any new information?”

“Professor Slughorn and I have been working on deconstructing it. It…it is not one of mine, Albus.”

Dumbledore smiled gently. “I imagine that that is a relief.”

Snape nodded.

“And yet, it makes analysing it more difficult?”

Snape nodded again. “The base looks to be something commercial—well, available in Knockturn Alley, at any rate—but it has been modified.”

“Could Draco have managed it?”

“Possible, but unlikely. Modifying it would have required, not only advanced knowledge, but a great deal of specialised equipment. Poisons can be tricky to work with. More likely he bought is from someone or…or commissioned it.”

Snape thought of Wormtail, holed up in Malfoy Manor. The manor had all the necessary equipment for poison-making—why, Snape himself had advised Lucius on what to buy, what sort of protective charms to place on the walls and floors, which reference manuals would be the most useful. The laboratory was hidden beneath one of the reflecting pools, and Snape imagined the filthy rat there now, secreted away underground, thumbing his nose at Snape as he stood over a simmering silver cauldron.

Dumbledore sighed. “Well, however he obtained it, his method of attempting to administer it was exceedingly crude. Keep after him, Severus. We can’t have any more students harmed.”

Snape gritted his teeth and nodded. He turned to leave, but before he reached the door, he asked, “Mister Weasley, he will make a full recovery, yes?”

Dumbledore’s face brightened. “Madam Pomfrey assures me that both boys will be well enough to return to their lessons on Monday.”

“Yes, well let us hope that what little knowledge I have managed to instil in Potter this year did not leak out when his skull split open.”

“He retains more than you give him credit for, Severus. He didn’t learn about bezoars from Horace or myself.”

No, Snape thought, he didn’t, but I’ll bet you anything he didn’t “retain” a damn thing—he read it in my old textbook. Aloud, he said, “You are right, Headmaster. Although I fear for the boy’s N.E.W.T. results if it takes him over five years to grasp everything I’ve taught him.” And without waiting to see whether this comment earned him a grimace or a smile, Snape left the room.

He told himself, again, that it had been a good thing that Dumbledore had cut him off that night in the Forbidden Forest before he’d had a chance to reveal his suspicions about Potter and his old textbook. After all, it would only have led to a lot of uncomfortable questions: Is the information accurate? Is it useful? Is it safe? Is there any reason not to let him keep it?

Snape knew that there were reasons not to let him keep it. However, Potter seemed to be sticking to the Potions-related advice. And, apart from showing off in class, the boy did not seem to be misusing the knowledge he’d gained. Snape would just have to keep a close watch on him, that was all.

*******

Except, that wasn’t all.

There were classes to teach and papers to mark and house matters that could not be ignored. There were Muggles in Surrey who expected letters. There were meetings with representatives from the board of governors and the Ministry and concerned parents’ organisations. There were meetings of the Order of the Phoenix. There were meetings with the Dark Lord. There were staff meetings.

Snape hardly knew whether he was coming or going at times, and he privately wondered how much longer till he turned up for a board meeting in full Death Eater garb or appeared before the Dark Lord with a fistful of testimonials as to why little Gerald and Iris and Xavier III were still much better off at Hogwarts, despite the recent troubles.

Snape did his best to keep an eye on both Draco and Potter, but he knew that he was missing something, and he didn’t know how to find out what it was. Near as he could tell, both boys skulked around the castle a great deal, but took care not to get caught. Both boys were, in turn, sullen or rude, and both boys seemed to be taking a cavalier attitude toward their studies of late (Potter’s pilfered Potions prowess aside). Potter and his freckled friend were lucky he hadn’t taken fifty points from Gryffindor for their "ghosts are transparent" twaddle in class the other day, and Draco had all but given up making excuses for the essays he handed in late (if at all). Sometimes he didn’t even bother to recopy what Miss Parkinson had written for him.

The problem was that Snape, even if he had been possessed of eyes in the back of his head, as was rumoured, could not possibly keep an eye on both boys at all times. He contemplated enlisting Fleagle’s aid, but quickly dismissed the idea as preposterous. It would be too much of an imposition on the house-elf’s regular duties, for one thing. Plus, the odds of Dumbledore finding out were too high, and Snape did not fancy explaining to the headmaster that he’d ordered a house-elf to follow Potter around on the off chance he started attacking his fellow students with Dark Magic that he’d learned out of Snape’s old textbook.

No, from here on out, Snape would handle everything by himself, the way he’d been taught to do.

And so Snape slogged on through the spring, attending to his numerous duties with an expression that would not have looked amiss on his mother’s face and a sheer bloody-mindedness that would have made his father proud. And if he had any regrets about his decision, he did not allow himself to dwell on them, not even when Dumbledore informed him that they were indeed up against Horcruxes, plural.

Not even when Dumbledore told him, gently, that he needn’t bother with the Dexter’s anymore, as it no longer brought any relief.

Not even when a sudden jolt of magical energy sent him racing toward the toilets on the sixth floor, knowing he had to get there—Now! Now! Now!—without knowing why.

Not even as he wiped the blood from Draco’s pale face and chanted the counter-curse, or as he peered into Potter’s mind and saw confirmation of all his suspicions, or as he lied (to Pomfrey and McGonagall and Dumbledore and Narcissa Malfoy) about where Potter had learned Sectumsempra.

As May progressed, Snape retreated further into himself. His fellow staff didn’t appear to mind much (he hadn’t been very pleasant to them of late), and Dumbledore, damn him, seemed to understand Snape’s need to remain apart. Fleagle was the only one who was upset, fearing he’d offended Snape somehow when Snape no longer called on him for wine or food or “sneaky sneaky” missions. Snape mollified the house-elf by extracting a promise that, no matter what happened, Fleagle would come once a week to dust the jars in Snape’s office, and that he would keep an eye out for anything in the castle bearing the words “Property of the Half-Blood Prince.”

The warmer weather brought the inevitable bloom, not only of wildflowers, but also of romance amongst the hormone-ridden students, and Snape watched it all from what felt like a great distance. True, the first time he caught Potter sitting there in detention with a secret smile on his face, he felt a stab of jealousy such as he had not known in decades, but it passed. By the time he heard that Potter had been seen on the grounds with Ginevra Weasley (the boy had the same tastes as his father, evidently), he found that he could not even summon the energy to be really vicious in his teasing of the boy. Let Potter snog whichever Weasley he would; it made no difference to Snape. He liked being alone—alone and self-sufficient.

Occasionally, the feel of the leather satchel, snug against his left side, would remind Snape that the idea that he could operate independently on an indefinite basis was sheer fantasy, and that he’d bloody well better start working out how he was going to push Petunia that extra inch, but he grew adept at pushing such thoughts aside, thinking, Do for yourself; do for yourself; do for yourself.

Life at Hogwarts had always involved routines, and Snape clung to them fiercely, nursing the secret hope that if he did not break them, things might, perhaps, just go on as they were.

Mondays through Fridays, he taught classes and made his rounds. Saturdays he caught up on his reading or marked essays, strangely comforted by the fact that Potter sat only a few feet away, safe, not out Horcrux-hunting with the headmaster or pursuing his own ill-informed theories.

On Sundays he took to having a lie-in, not sleeping so much as lying on his back and staring at the ceiling. He did not allow himself to get out of bed—not even to relieve himself—until he was very, very sure that he’d squashed any and all urges to go to Dumbledore and confess everything, as he had done on that night so long ago.

It had made all the difference then, but it wouldn’t do any good now. It would only upset Dumbledore; it might even weaken him or make him despair, and Snape didn’t want that. Snape might not know whether or not he would actually follow through on all the promises he’d made to the headmaster, but he would never wish Dumbledore ill. Better to wait and see what would happen. Better to wait and see…

Who wins? a cynical voice said inside Snape’s mind. Why bother? It won’t be you. Better haul your arse out of bed before you wet it and get along to the Great Hall before all the bacon is gone. Do for yourself, remember?

And Snape listened to that voice, every time—every time, that is, until one night in June, when Professor Flitwick burst into Snape’s office babbling about Death Eaters and a savage werewolf in the castle, and Snape, who had felt queasy all evening but had put it down to the fish stew they’d had for dinner, suddenly knew that he’d only been fooling himself. He also knew, without a doubt, that he would never have a second chance at this night. Not ever.

He Stupefied his colleague from behind—Flitwick was an expert at Charms, but no match for Fenrir and a gang of Death Eaters—and raced out into the corridor. He was surprised to see Granger and Lovegood, but the thought of Fenrir catching sight of either of them brought an easy lie to his lips, and they immediately rushed into his office to see to Flitwick. He hoped they’d have the sense to stay there.

He blinked, took a deep breath, and then he was off, running. He didn’t know whether it was the traces of Dark Magic or the pull of the Unbreakable Vow that led him, but soon he was sprinting up the narrow staircase of the Astronomy Tower as if Fluffy were on his heels, not even pausing to wonder why, although the stairs spiralled higher and higher, he felt like he was descending into a crypt.

*******