Malfoy doesn't reappear in classes until late on Thursday morning, when the Slytherins and Gryffindors are halfway through double Potions.
He swaggers into the dungeon, his right arm covered in bandages and bound up in a sling, acting, in Harry's opinion, as though he is the heroic survivor of some dreadful battle.
"How is it, Draco?" Simpers Pansy Parkinson. "Does it hurt much?"
"Yeah," says Malfoy, putting on a brave sort of grimace. But Harry sees him wink at Crabbe and Goyle when Pansy looks away.
"Settle down, settle down," says Professor Snape idly.
Harry and Ron scowl at each other; Snape wouldn't say 'settle down' if they walked in late, he'd have given them detention.
But Malfoy has always been able to get away with anything in Snape's classes; Snape is Head of Slytherin house, and generally favoured his own students before all others.
They are making a new potion today, a Shrinking Solution. Malfoy sets up his cauldron right next to Harry and Ron, so that they are preparing their ingredients on the same table.
"Sir," Malfoy calls, "sir, I'll need help cutting up these daisy roots, because of my arm -"
"Weasley, cut up Malfoy's roots for him," says Snape, without looking up.
Ron goes brick red.
"There's nothing wrong with your arm," he hisses at Malfoy.
Malfoy smirks across the table.
"Weasley, you heard Professor Snape, cut up these roots."
Ron seizes his knife, pulls Malfoy's roots towards him and begins to chop them roughly, so that they are all different sizes.
"Professor," drawls Malfoy, "Weasley's mutilating my roots, sir."
Snape approaches their table, stares down his hooked nose at the roots, then gives Ron an unpleasant smile from beneath his long, greasy black hair.
"Change roots with Malfoy, Weasley."
"But sir -!"
Ron has spent the last quarter of an hour carefully shredding his own roots into exactly equal pieces.
"Now," says Snape in his most dangerous voice.
Ron shoves his own beautifully cut roots across the table at Malfoy, then takes up the knife again.
"And, sir, I'll need this Shrivelfig skinned," says Malfoy, his voice full of malicious laughter.
"Potter, you can skin Malfoy's Shrivelfig," says Snape, giving Harry the look of loathing he always reserves just for him.
Harry takes Malfoy's Shrivelfig as Ron sets about trying to repair the damage to the roots he now has to use.
Harry skins the Shrivelfig as fast as he can and fling it back across the table at Malfoy without speaking.
Malfoy is smirking more broadly than ever.
"Seen your pal Hagrid lately?" he asks them quietly.
"None of your business," says Ron jerkily, without looking up.
"I'm afraid he won't be a teacher much longer," says Malfoy, in a tone of mock sorrow. "Father's not very happy about my injury -"
"Keep talking, Malfoy, and I'll give you a real injury," snarls Ron.
"- he's complained to the school governors. And to the Ministry of Magic. Father's got a lot of influence, you know. And a lasting injury like this -" he gives a huge, fake sigh, "who knows if my arm'll ever be the same again?"
"So that's why you're putting it on," says Harry, accidentally beheading a dead caterpillar because his hand is shaking in anger. (Oof)
"To try and get Hagrid sacked."
"Well," says Malfoy, lowering his voice to a whisper, "partly, Potter. But there are other benefits, too. Weasley, slice my caterpillars for me."
A few cauldrons away, Neville is in trouble. Neville regularly goes to pieces in Potions lessons; it is his worst subject, and his great fear of Professor Snape makes things ten times worse. His potion, which is supposed to be a bright, acid green, has turned -
"Orange, Longbottom," says Snape, ladling some up and allowing it to splash back into the cauldron, so that everyone can see. "Orange. Tell me, boy, does anything penetrate that thick skull of yours? Didn't you hear me say, quite clearly, that only one rat spleen was needed? Didn't I state plainly that a dash of leech juice would suffice? What do I have to do to make you understand, Longbottom?"
Neville is pink and trembling. He looks like he is on the verge of tears.
"Please, sir," says Hermione, "please, I could help Neville put it right -"
"I don't remember asking you to show off, Miss Granger," says Snape coldly, and Hermione goes as pink as Neville.
"Longbottom, at the end of this lesson we will feed a few drops of this potion to your toad and see what happens.
Perhaps that will encourage you to do it properly."
Snape moves away, leaving Neville breathless with fear. "Help me," he moans to Hermione.
"Hey, Harry," says Seamus Finnigan, leaning over to borrow Harry's brass scales, "have you heard? Daily Prophet this morning - they reckon Sirius Black's been sighted."
"Where?" says Harry and Ron quickly.
On the other side of the table, Malfoy looks up, listening closely.
"Not too far from here," says Seamus, who looks excited. "It was a Muggle who saw him. 'Course, she didn't really understand. The Muggles think he's just an ordinary criminal, don't they? So she 'phoned the telephone hotline. By the time the Ministry of Magic got there, he was gone."
"Not too far from here ..." Ron repeats, looking significantly at Harry. He turns around and sees Malfoy watching closely. "What, Malfoy? Need something else skinning?"
But Malfoy's eyes are shining malevolently, and they are fixed on Harry. He leans across the table. "Thinking of trying to catch Black single-handed, Potter?"
"Yeah, that's right," says Harry offhandedly.
Malfoy's thin mouth is curving in a mean smile.
"Of course, if it was me," he says quietly, "I'd have done something before now. I wouldn't be staying in school like a good boy, I'd be out there looking for him."
"What are you talking about, Malfoy?" says Ron roughly.
"Don't you know, Potter?" breathes Malfoy, his pale eyes narrow.
"Know what?"
Malfoy lets out a low, sneering laugh. "Maybe you'd rather not risk your neck," he says. "Want to leave it to the Dementors, do you? But if it was me, I'd want revenge. I'd hunt him down myself."
"What are you talking about?" says Harry angrily, but at that moment Snape calls, "You should have finished adding your ingredients by now. This potion needs to stew before it can be drunk; clear away while it simmers and then we'll test Longbottom's ..."
Crabbe and Goyle laugh openly, watching Neville sweat as he stirs his potion feverishly. Hermione is muttering instructions to him out of the corner of her mouth, so that Snape can't see.
Harry and Ron pack away their unused ingredients and go to wash their hands and ladles in the stone basin in the corner.
"What did Malfoy mean?" Harry mutters to Ron, as he sticks his hands under the icy jet that pours from a gargoyle's mouth. "Why would I want revenge on Black? He hasn't done anything to me - yet."
"He's making it up," says Ron, savagely, "he's trying to make you do something stupid ..."
With the end of the lesson in sight, Snape strides over to Neville, who is cowering by his cauldron.
"Everyone gather round," says Snape, his black eyes glittering, "and watch what happens to Longbottom's toad. If he has managed to produce a Shrinking Solution, it will shrink to a tadpole. If, as I don't doubt, he has done it wrong, his toad is likely to be poisoned."
The Gryffindors watch fearfully. The Slytherins look excited. Snape picks up Trevor the toad in his left hand, and dips a small spoon into Neville's potion, which is now green. He trickles a few drops down Trevor's throat.
There is a moment of hushed silence, in which Trevor gulps; then there is a small pop, and Trevor the tadpole is wriggling in Snape's palm.
The Gryffindors burst into applause. Snape, looking sour, pulls a small bottle from the pocket of his robe, pours a few drops on top of Trevor and he reappears suddenly, fully grown.
"Five points from Gryffindor," says Snape, which wipes the smiles from everyone's face. "I told you not to help him, Miss Granger. Class dismissed."
Harry, Ron and Hermione climb the steps to the Entrance Hall. Harry is still thinking about what Malfoy said, while Ron is seething about Snape.
"Five points from Gryffindor because the potion was all right! Why didn't you lie, Hermione? You should've said Neville did it all by himself!"
Hermione doesn't answer.
Ron looks around.
"Where is she?"
Harry turns, too.
They are at the top of the steps now, watching the rest of the class pass them, heading for the Great Hall and lunch.
"She was right behind us," says Ron, frowning.
Malfoy passes them, walking between Crabbe and Goyle. He smirks at Harry and disappears.
"There she is," says Harry.
Hermione is panting slightly, hurrying up the stairs; one hand is clutching her bag, the other seems to be tucking something down the front of her robes.
"How did you do that?" says Ron.
"What?" says Hermione, joining them.
"One minute you were right behind us, and the next, you were back at the bottom of the stairs again."
"What?" Hermione looks slightly confused. "Oh - I had to go back for something. Oh, no ..."
A seam has split on Hermione's bag.
Harry isn't surprised; he can see that it is crammed with at least a dozen large and heavy books.
"Why are you carrying all these around with you?" Ron asks her.
"You know how many subjects I'm taking," says Hermione breathlessly. "Couldn't hold these for me, could you?"
"But -" Ron is turning over the books she handed him, looking at the covers "- you haven't got any of these subjects today. It's only Defence Against the Dark Arts this afternoon."
"Oh, yes," says Hermione vaguely, but she packs all the books back into her bag just the same. "I hope there's something good for lunch, I'm starving," she adds, and she marches off towards the Great Hall.
"D'you get the feeling Hermione's not telling us something?" Ron asks Harry.
Timeskip
Professor Lupin isn't there when they arrive at his first Defence Against the Dark Arts lesson. The only person who is there is Polaris, who explains why he's in there "I managed to cut a deal with Dumbledore," he whispers to Harry, Ron and Hermione.
"where I only take one elective in exchange for being a teacher's assistant. I only do it for Care of Magical Creatures, and Defence Against The Dark Arts because I know a lot about these subjects, and I kind of want to teach someday." he continues, straightening his green and silver tie.
"It also allows me to keep an eye on Draco, in case he decides to cause a disturbance." Polaris adds quickly, hearing Lupin enter the classroom.
Lupin smiles vaguely and places his tatty old briefcase on the teacher's desk. He is as shabby as ever but looks healthier than he did on the train, like he's had a few square meals.
"Good afternoon," he says. "Would you please put all your books back in your bags. Today will be a practical lesson. You will only need your wands."
A few curious looks are exchanged as the class puts away their books. They have never had a practical Defence Against the Dark Arts before, unless you count the memorable class last year when their old teacher brought a cageful of pixies to class and set them loose.
"Right then," says Professor Lupin, when everyone is ready, "if you'd follow me and Polaris here."
Puzzled but interested, the class gets to its feet and follows Professor Lupin and Polaris out of the classroom.
They lead them along the deserted corridor and around a corner, where the first thing they see is Peeves the poltergeist, who is floating upside-down in mid-air and stuffing the nearest keyhole with chewing gum.
Peeves doesn't look up until Professor Lupin is two feet away, then he wiggles his curly-toed feet and breaks into song.
"Loony, loopy Lupin," Peeves sings. "Loony, loopy Lupin, loony, loopy Lupin -"
Rude and unmanageable as he almost always is, Peeves usually shows some respect towards the teachers.
Everyone looks quickly at Professor Lupin to see how he'll take this; to their surprise, he is still smiling.
"I'd take that gum out of the keyhole, if I were you, Peeves," he says pleasantly. "Mr Filch won't be able to get in to get his brooms."
Filch is the Hogwarts caretaker, a bad-tempered, failed wizard who wages a constant war against the students and, indeed, Peeves.
However, Peeves pays no attention to Professor Lupin's words, except to blow a loud wet raspberry.
Professor Lupin gives a small sigh and takes out his wand.
"This is a useful little spell," he tells the class over his shoulder. "Please watch closely."
He raises the wand to shoulder height, says "Waddiwasi!" and points it at Peeves.
With the force of a bullet, the wad of chewing gum shoots out of the keyhole and straight down Peeves's left nostril;
he whirls right way up and zooms away, cursing.
"Cool, sir!" says Dean Thomas in amazement.
"Thank you, Dean," says Professor Lupin, putting his wand away again. "Shall we proceed?"
They set off again, the class looking at shabby Professor Lupin with increasing respect.
Him and Polaris lead them down a second corridor and stop, right outside the staff-room door.
"Inside, please," says Professor Lupin, opening it and standing back.
The staff room, a long, panelled room full of old, mismatched chairs, is empty except for one teacher. Professor Snape is sitting in a low armchair, and he looks around as the class fills in.
His eyes are glittering and there is a nasty sneer playing around his mouth.
As Professor Lupin comes in and goes to close the door behind him, Snape says, "Leave it open, Lupin. I'd rather not witness this."
He gets to his feet and strides past the class, his black robes billowing behind him.
At the doorway he turns on his heel and says, "Possibly no one's warned you, Lupin, but this class contains Neville Longbottom. I would advise you not to entrust him with anything difficult. Not unless Miss Granger is hissing instructions in his ear."
Neville goes scarlet.
Harry glares at Snape; it is bad enough that he bullies Neville in his own classes, let alone doing it in front of other teachers.
Professor Lupin raises his eyebrows, while Polaris looks at Neville and says "If you want some help with potions, feel free to ask me, I don't mind." Neville looks at him gratefully and nods his head.
Snape's lip curls, but he leaves, shutting the door with a snap.
"Now, then," says Professor Lupin, beckoning the class towards the end of the room, where there is nothing except an old wardrobe in which the teachers keep their spare robes.
As Professor Lupin goes to stand next to it, the wardrobe gives a sudden wobble, banging off the wall.
"Nothing to worry about," says Professor Lupin calmly, as a few people jump backwards in alarm. "There's a Boggart in there."
Most people seem to feel that this is something to worry about. Neville gives Professor Lupin a look of pure terror, and Seamus Finnigan eyes the now rattling doorknob apprehensively.
"Boggarts like dark, enclosed spaces," says Professor Lupin. "Wardrobes, the gap beneath beds, the cupboards under sinks - I once met one that had lodged itself in a grandfather clock. This one moved in yesterday afternoon, and I asked the Headmaster if the staff would leave it to give my third-years some practice. So, the first question we must ask ourselves is, what is a Boggart?"
Hermione puts up her hand.
"It's a shape-shifter," she says. "It can take the shape of whatever it thinks will frighten us most."
"Couldn't have put it better myself," says Professor Lupin, and Hermione glows.
"So the Boggart sitting in the darkness within has not yet assumed a form. He does not yet know what will frighten the person on the other side of the door. Nobody knows what a Boggart looks like when he is alone, but when I let him out, he will immediately become whatever each of us fear the most. This means," says Professor Lupin, choosing to ignore Neville's small splutter of terror, "that we have a huge advantage over the Boggart before we begin. Have you spotted it, Harry?"
Trying to answer a question with Hermione next to him, bobbing up and down on the balls of her feet with her hand in the air, is very off-putting, but Harry has a go.
"Er - because there are so many of us, it won't know what shape it should be?"
"Exactly," says Professor Lupin, and Hermione puts her hand down looking a little disappointed. "It's always best to have company when you're dealing with a Boggart. They become confused. Which should he become, a headless corpse or a flesh-eating slug? I once saw a Boggart make that very mistake - tried to frighten two people at once and turned himself into half a slug. Not remotely frightening."
"The charm that repels a Boggart is simple, yet it requires force of mind. You see, the thing that really finishes a Boggart is laughter. What you need to do is force it to assume a shape that you find amusing. We will practise the charm without wands first. After me, please ... riddikulus!"
"Riddikulus!" says the class together.
"Good," says Professor Lupin. "Very good. But that was the easy part, I'm afraid. You see, the word alone is not enough. And this is where you come in, Polaris."
The wardrobe shakes again, this time more violently.
"Right, Polaris," says Professor Lupin. "First things first: what would you say is the thing that frightens you most in the world?"
Polaris just looks at Lupin and says in his mind: "I don't feel comfortable saying it out loud" Professor Lupin looks thoughtful and nods and replies "Don't worry about it, just tell me like this" Polaris nods and says "I'm scared of becoming like my parents."
Professor Lupin looks at Polaris with sympathy, and says "Alright, understandable, now think of a way to make it funny."
Polaris closes his eyes for a moment and gets an idea "Alright, I have an idea."
"Great, now when the Boggart bursts out of this wardrobe, and sees you, it will assume the form of what you fear," says Lupin. "And you will raise your wand - thus - and cry "Riddikulus" - and concentrate hard on your idea. If all goes well, the Boggart will be forced into whatever you're thinking of."
Polaris nods and reaches into his robes and pulls out his wand, the silver snake is still wrapped around it.
"If Polaris is successful, the Boggart is likely to turn his attention to each of us in turn," says Professor Lupin.
"I would like all of you to take a moment now to think of the thing that scares you most, and imagine how you might force it to look comical ..."
The room goes quiet. Harry thinks to himself: What scares him most in the world?
His first thought is Lord Voldemort - a Voldemort returned to full strength. But before he has even started to plan a possible counter-attack on a Boggart-Voldemort, a horrible image comes floating to the surface of his mind ...
A rotting, glistening hand, slithering back beneath a black cloak ... a long, rattling breath from an unseen mouth ... then a cold so penetrating it felt like drowning ...
Harry shivers, then looks around, hoping no one noticed. Many people have their eyes shut tight. Ron is muttering to himself, 'Take its legs off.' Harry is sure he knows what that is about. Ron's greatest fear is spiders.
"Everyone ready?" says Professor Lupin.
Harry feels a lurch of fear. He isn't ready. How can you make a Dementor less frightening? But he doesn't want to ask for more time; everyone else is nodding and rolling up their sleeves.
"Polaris, we're going to back away," says Professor Lupin. "Let you have a clear field, all right? I'll call the next person forward ... everyone back, now, so he can get a clear shot -"
They all retreat, backing against the walls, leaving Polaris alone beside the wardrobe. He looks determined, and pushes up the sleeves of his robes and is holding his wand ready.
"On the count of three, Polaris," says Professor Lupin, who is pointing his own wand at the handle of the wardrobe. "One - two - three - now!"
A jet of sparks shot out from the end of Professor Lupin's wand and hit the doorknob.
The wardrobe bursts open. And what steps out surprises almost everyone: the Boggart has taken the form of Polaris, but their hair is way curlier, their eyes are magenta instead of purple, their robes are torn and covered in blood stains, and they are smiling sadistically.
Polaris doesn't seem to flinch, he just raises his wand and says "Riddikulus!" and there is a noise like a whip-crack. 'Polaris' suddenly starts to perform cartwheels.
There is a roar of laughter; the Boggart pauses, confused, and Professor Lupin shouts, "Neville! Forward!"
Neville walks forward like he is heading for the gallows. 'Polaris' rounds on him. There is another crack, and Professor Snape is now standing where the fake Polaris stood just a second ago.
"R-r-riddikulus!" squeaks Neville.
'Snape' stumbles; he is suddenly wearing a long, lace-trimmed dress and a towering hat topped with a moth-eaten vulture, and swinging a huge crimson handbag from his hand.
"Parvati!" roars Professor Lupin.
Crack!
'Snape' is replaced by a bloodstained, bandaged mummy; its sightless face is turned to Parvati and it begins to walk towards her, very slowly, dragging its feet, its stiff arms rising -
"Riddikulus!" cries Parvati.
A bandage unravels at the mummy's feet; it becomes entangled, falls face forwards and its head rolls off.
"Seamus!" shouts Professor Lupin.
Seamus darts past Parvati.
Crack!
Where the mummy was is a woman with floor-length black hair and a skeletal, green-tinged face - a banshee. She opens her mouth wide, and an unearthly sound filled the room, a long, wailing shriek which makes the hair on Harry's head stand on end -
"Riddikulus!" Seamus shouts.
The banshee makes a rasping noise and clutches her throat; her voice is gone.
Crack!
The banshee turns into a rat, which chases its tail in a circle, then - crack! - becomes a rattlesnake, which slithers and writhes before - crack! - becoming a single, bloody eyeball.
"It's confused!" Lupin shouts. "We're getting there! Dean!"
Dean hurries forward.
Crack!
The eyeball becomes a severed hand, which flips over, and begins to creep along the floor like a crab.
"Riddikulus!" Dean yells.
There is a snap, and the hand is trapped in a mousetrap.
"Excellent! Ron, you next!"
Ron leaps forward.
Crack!
Quite a few people scream. A giant spider, six feet tall and covered in hair, is advancing on Ron, clicking its pincers menacingly. For a moment, Harry thinks Ron has frozen.
Then -
"Riddikulus!" Ron bellows, and the spider's legs vanish. It rolls over and over; Lavender Brown squeals and runs out of its way and it comes to a halt at Harry's feet. He raises his wand, ready, but -
"Here!" shouts Professor Lupin suddenly, hurrying forward.
Crack!
The legless spider vanishes. For a second, everyone looks wildly around to see where it is. Then they see a silvery white orb hanging in the air in front of Lupin, who says "Riddikulus!" almost lazily.
Crack!
"Forward, Polaris, and finish him off!" says Lupin, as the Boggart lands on the floor as a cockroach.
Crack!
'Polaris' is back. The real Polaris charges forward looking determined.
"Riddikulus!" he shouts, and they have a split second's view of himself in the middle of a cartwheel before he starts chuckling at himself.
The Boggart explodes, bursts into a thousand tiny wisps of smoke, and is gone.
"Excellent!" cries Professor Lupin, as the class breaks into applause. "Excellent, Polaris. Well done, everyone. Let me see ... five points to every person to tackle the Boggart - ten for Polaris because he did it twice - and five each to Hermione and Harry."
"But I didn't do anything," says Harry.
"You and Hermione answered my questions correctly at the start of the class, Harry," Lupin says lightly. "Very well, everyone, an excellent lesson. Homework, kindly read the chapter on Boggarts and summarise it for me ... to be handed in on Monday. That will be all."
Talking excitedly, the class leaves the staff room. Harry, however, isn't feeling cheerful. Professor Lupin deliberately stopped him tackling the Boggart. Why? Was it because he'd seen Harry collapse on the train, and thought he wasn't up to much? Had he thought Harry would pass out again?
But no one else seems to notice anything.
"Did you see me take that banshee?" Seamus shouts.
"And the hand!" says Dean, waving his own around.
"And Snape in that hat!"
"And my mummy!"
"I wonder why Professor Lupin's frightened of crystal balls?" says Lavender thoughtfully.
"That was the best Defence Against the Dark Arts lesson we've ever had, wasn't it?" says Ron excitedly, as they make their way back to the classroom to get their bags.
"He seems like a very good teacher," says Hermione approvingly. "But I wish I could have had a turn with the Boggart -"
"What would it have been for you?" says Ron, sniggering. "A piece of homework that only got nine out of ten?"