Professor Lupin wasn't there when they arrived at his first Defense Against the Dark Arts lesson. They all sat down, took out their books, quills, and parchment, and were talking when he finally entered the room. Lupin smiled vaguely and placed his tatty old briefcase on the teacher's desk. He was as shabby as ever but looked healthier than he had on the train, as though he had had a few square meals.

"Good afternoon," he said. "Would you please put all your books back in your bags. Today's will be a practical lesson. You will need only your wands."

A few curious looks were exchanged as the class put away their books. They had never had a practical Defense Against the Dark Arts class before, unless you counted the memorable class last year when Gilderoy Lockhart had brought a cageful of pixies to class and set them loose.

"Right then," said Professor Lupin, when everyone was ready. "If you'd follow me."

Puzzled but interested, the class got to its feet and followed Professor Lupin out of the classroom. He led them along the deserted corridor and around a corner, where the first thing they saw was Peeves the Poltergeist, who was floating upside down in midair and stuffing the nearest keyhole with chewing gum.

Peeves didn't look up until Professor Lupin was two feet away; then he wiggled his curly-toed feet and broke into song.

"Loony, loopy Lupin," Peeves sang. "Loony, loopy Lupin, loony, loopy Lupin -"

Rude and unmanageable as he almost always was, Peeves usually showed some respect toward the teachers. Everyone looked quickly at Professor Lupin to see how he would take this; to their surprise, he was still smiling.

"I'd take that gum out of the keyhole if I were you, Peeves," he said pleasantly. "Mr. Filch won't be able to get in to his brooms."

Filch was the Hogwarts caretaker, a bad-tempered, failed wizard who waged a constant war against the students and, indeed, Peeves. However, Peeves paid no attention to Professor Lupin's words, except to blow a loud wet raspberry.

Professor Lupin gave a small sigh and took out his wand.

"This is a useful little spell," he told the class over his shoulder. "Please watch closely."

He raised the wand to shoulder height, said, "Waddiwasi!" and pointed it at Peeves.

With the force of a bullet, the wad of chewing gum shot out of the keyhole and straight down Peeves's left nostril; he whirled upright and zoomed away, cursing.

"Cool, sir!" said Dean Thomas in amazement.

"Thank you, Dean," said Professor Lupin, putting his wand away again. "Shall we proceed?"

They set off again, the class looking at shabby Professor Lupin with increased respect. He led them down a second corridor and stopped, right outside the staffroom door.

"Inside, please," said Professor Lupin, opening it and standing back.

The staffroom, a long, paneled room full of old, mismatched chairs, was empty except for one teacher. Professor Snape was sitting in a low armchair, and he looked around as the class filed in. His eyes were glittering and there was a nasty sneer playing around his mouth. As Professor Lupin came in and made to close the door behind him, Snape said, "Leave it open, Lupin. I'd rather not witness this." He got to his feet and strode past the class, his black robes billowing behind him. At the doorway he turned on his heel and said, "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 went scarlet.

Professor Lupin had raised his eyebrows.

"I was hoping that Neville would assist me with the first stage of the operation," he said, "and I am sure he will perform it admirably."

Neville's face went, if possible, even redder. Snape's lip curled, but he left, shutting the door with a snap.

"Now, then," said Professor Lupin, beckoning the class toward the end of the room, where there was nothing but an old wardrobe where the teachers kept their spare robes. As Professor Lupin went to stand next to it, the wardrobe gave a sudden wobble, banging off the wall.

"Nothing to worry about," said Professor Lupin calmly because a few people had jumped backward in alarm. "There's a Boggart in there."

Most people seemed to feel that this was something to worry about. Neville gave Professor Lupin a look of pure terror, and Seamus Finnigan eyed the now rattling doorknob apprehensively.

"Boggarts like dark, enclosed spaces," said Professor Lupin. "Wardrobes, the gap beneath beds, the cupboards under sinks - I've even 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 put up her hand.

"It's a shape-shifter," she said. "It can take the shape of whatever it thinks will frighten us most."

"Couldn't have put it better myself," said Professor Lupin, and Hermione glowed. "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 most fears.

"This means," said Professor Lupin, choosing to ignore Neville's small sputter of terror, "that we have a huge advantage over the Boggart before we begin. Have you spotted it, Dudley?"

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, was very off-putting, and Dudley wasn't the quickest of thinkers at the best of times.

"Er - because we can work together to beat it?"

"Well—yes, but how does that help us?"

Dudley frowned. "I guess … hang on. You said it turns into what we fear?"

Lupin nodded.

"So … if there are lots of us, it won't know what to turn into?" Dudley guessed.

"Precisely," said Professor Lupin, and Hermione put her hand down, looking a little disappointed. "It's always best to have company when you're dealing with a Boggart. He becomes 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 practice the charm without wands first. After me, please...riddikulus!"

"Riddikulus!" said the class together.

"Good," said 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, Neville."

The wardrobe shook again, though not as much as Neville, who walked forward as though he were heading for the gallows.

"Right, Neville," said Professor Lupin. "First things first: what would you say is the thing that frightens you most in the world?"

Neville's lips moved, but no noise came out.

"I didn't catch that, Neville, sorry," said Professor Lupin cheerfully.

Neville looked around rather wildly, as though begging someone to help him, then said, in barely more than a whisper, "Professor Snape."

Nearly everyone laughed. Even Neville grinned apologetically. Professor Lupin, however, looked thoughtful.

"Professor Snape...hmmm...Neville, I believe you live with your grandmother?"

"Er - yes," said Neville nervously. "But - I don't want the Boggart to turn into her either."

"No, no, you misunderstand me," said Professor Lupin, now smiling. "I wonder, could you tell us what sort of clothes your grandmother usually wears?"

Neville looked startled, but said, "Well...always the same hat. A tall one with a stuffed vulture on top. And a long dress...green, normally...and sometimes a fox-fur scarf."

"And a handbag?" prompted Professor Lupin.

"A big red one," said Neville.

"Right then," said Professor Lupin. "Can you picture those clothes very clearly, Neville? Can you see them in your mind's eye?"

"Yes," said Neville uncertainty, plainly wondering what was coming next.

"When the Boggart bursts out of this wardrobe, Neville, and sees you, it will assume the form of Professor Snape," said Lupin. "And you will raise your wand - thus - and cry "Riddikulus" - and concentrate hard on your grandmother's clothes. If all goes well, Professor Boggart Snape will be forced into that vulture-topped hat, and that green dress, with that big red handbag."

There was a great shout of laughter. The wardrobe wobbled more violently.

"If Neville is successful, the Boggart is likely to shift his attention to each of us in turn," said 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 went quiet. Dudley thought...What scared him most in the world?

A few things went through his mind—Voldemort, a troll, fighting Quirrell. He finally settled on the basilisk. Coming face to face with that thing had been terrifying.

Many people had their eyes shut tight. Ron was muttering to himself, "Take its legs off." Dudley was sure he knew what that was about. Ron's greatest fear was spiders.

"Everyone ready?" said Professor Lupin.

Dudley gave a small nod. The way to make a basilisk less frightening must be to get rid of its eyes. He decided he would think about its eyes falling out.

"Neville, we're going to back away," said Professor Lupin. "Let you have a clear field, all right? I'll call the next person forward...Everyone back, now, so Neville can get a clear shot -"

They all retreated, backed against the walls, leaving Neville alone beside the wardrobe. He looked pale and frightened, but he had pushed up the sleeves of his robes and was holding his wand ready.

"On the count of three, Neville," said Professor Lupin, who was pointing his own wand at the handle of the wardrobe. "One - two - three - now!"

A jet of sparks shot from the end of Professor Lupin's wand and hit the doorknob. The wardrobe burst open. Hook-nosed and menacing, Professor Snape stepped out, his eyes flashing at Neville.

Neville backed away, his wand up, mouthing wordlessly. Snape was bearing down upon him, reaching inside his robes.

"R - r - riddikulus! " squeaked Neville.

There was a noise like a whip crack. Snape stumbled; he was wearing a long, lace-trimmed dress and a towering hat topped with a moth-eaten vulture, and he was swinging a huge crimson handbag.

There was a roar of laughter; the Boggart paused, confused, and Professor Lupin shouted, "Parvati! Forward!"

Parvati walked forward, her face set. Snape rounded on her. There was another crack, and where he had stood was a bloodstained, bandaged mummy; its sightless face was turned to Parvati and it began to walk toward her very slowly, dragging its feet, its stiff arms rising -

"Riddikulus!" cried Parvati.

A bandage unraveled at the mummy's feet; it became entangled, fell face forward, and its head rolled off.

"Seamus!" roared Professor Lupin.

Seamus darted past Parvati.

Crack! Where the mummy had been was a woman with floorlength black hair and a skeletal, green-tinged face - a banshee. She opened her mouth wide and an unearthly sound filled the room, a long, wailing shriek that made the hair on Dudley's head stand on end - "Riddikulus!" shouted Seamus.

The banshee made a rasping noise and clutched her throat; her voice was gone.

Crack! The banshee turned into a rat, which chased its tail in a circle, then - crack!- became a rattlesnake, which slithered and writhed before - crack! - becoming a single, bloody eyeball.

"It's confused!" shouted Lupin. "We're getting there! Dean!"

Dean hurried forward.

Crack! The eyeball became a severed hand, which flipped over and began to creep along the floor like a crab.

"Riddikulus!" yelled Dean.

There was a snap, and the hand was trapped in a mousetrap.

"Excellent! Ron, you next!"

Ron leapt forward.

Crack!

Quite a few people screamed. A giant spider, six feet tall and covered in hair, was advancing on Ron, clicking its pincers menacingly. For a moment, Dudley thought Ron had frozen. Then -

"Riddikulus!" bellowed Ron, and the spider's legs vanished; it rolled over and over; Lavender Brown squealed and ran out of its way and it came to a halt at Dudley's feet. He raised his wand, ready, but instead of the expected basilisk.

Crack!

It was Ron Weasley "We're not really friends with you, you fat oaf!"

Which then became Dean.

"Yeah, why would we be friends with you."

"You're nothing but a fat, stupid bully," the boggart was Hermione now.

"Ri … riddikklus!" Dudley shouted. Nothing happenend.

"People only pretend to be your friend because they're scared of you," the form was of Neville.

"Riddikulus!"

'You've always been nothing but a disappointment!" Vernon boomed.

Lupin stepped forward.

The figure of Vernon Dursley vanished. For a second, everyone looked wildly around to see where it was. Then they saw a silvery-white orb hanging in the air in front of Lupin, who said, "Riddikulus!" almost lazily.

Crack!

"Forward, Neville, and finish him off!" said Lupin as the Boggart landed on the floor as a cockroach. Crack! Snape was back. This time Neville charged forward looking determined.

"Riddikulus!" he shouted, and they had a split second's view of Snape in his lacy dress before Neville let out a great "Ha!" of laughter, and the Boggart exploded, burst into a thousand tiny wisps of smoke, and was gone.

"Excellent!" cried Professor Lupin as the class broke into applause. "Excellent, Neville. Well done, everyone...Let me see...five points to Gryffindor for every person to tackle the Boggart - ten for Neville because he did it twice...and five to Hermione."

Dudley felt shaken and surprised. He had been expecting a basilisk. But what did that mean? Was he really afraid of not being accepted, of his friends turning on him?

"Are you alright, Dudley?" Lupin asked, kindly.

"Yeah, yeah … it's just a boggart," Dudley said.

Lupin looked thoughtful. He lowered his voice. "You know, it is natural to feel worried about things like that, but let me assure you—you don't need to be. Treasure the time you spend with your friends, Dudley."

"Thanks, Professor, but I'm fine," he grabbed his things and headed out of the classroom where Ron, Dean and Hermione were waiting.

"Dud …" Hermione began.

"I'm fine," Dudley said, shortly.

"Listen, mate …" Ron began.

"I know, it's fine," Dudley said.

"No, listen," Ron grabbed Dudley by the robes. "That's just a boggart—me and Dean would never think that, right?"

"Right," Dean nodded. "You're our mate, Dud."

Dudley forced a smile. He still felt shaken by what the boggart had revealed and, a little embarrassed that that was his greatest fear. "I'm fine, seriously."

And changing the subject, he looked at Neville. "Yours was the best, Nev—Snape in a dress. Brilliant!"

The tension gone, they all laughed at the memory.

"He seems like a very good teacher," said Hermione approvingly. "But I wish I could have had a turn with the Boggart -"

"What would it have been for you?" said Ron, sniggering. "A piece of homework that only got nine out of ten?"

They all laughed again.

"Are you really so afraid of Snape?" Dean asked, Neville.

Neville looked embarrassed but didn't reply.

"You should stand up to him," Dean advised.

"I'd rather face Slytherin's monster again than do that," Ron had said. "You've got to be crazy to stand up to Snape."

"I'm with Dean," Dudley said. "Next time he tries pushing you around, just give him the finger."

They laughed at that, Neville included.

Hermione looked thoughtful. "Maybe that would be too far," she said, seriously. "But maybe you could try telling him to leave you alone. What's the worst that could happen?"

"A week's worth of detentions, losing points, getting expelled, being forced to drink some horrible potion …" Ron listed. "Just get better at potions, then he'll stop being such a …"

"Git," supplied Dean.

As they passed by the charms classroom, a bunch of Ravenclaws were stood outside, including Luna Lovegood.

"Dudley!" she said, loudly. She was wearing her earrings, which Dudley now recognized as being dirigible plums and a necklace of butterbeer corks.

"Did you like the jam I sent you? I made it myself."

"Oh, yeah, delicious," Dudley lied.

Luna beamed at him. "Well, you're in luck—I can get daddy to send more."

"Thanks, Luna," Dudley said. He moved to continue on his way.

"I'm glad we can talk here," Luna said. "I wanted to thank you for saving me from Slytherin's basilisk. It was very brave of you."

Dudley enjoyed hearing praise for his deeds but, for some reason, felt embarrassed. Maybe it was because Luna was so open about or because there were so many people gathered around. Or maybe it was because Ron and Dean were grinning.

"Well, we all helped," he said. "Ron 's the one who tried to curse Riddle to oblivion."

Ron's ears turned red as Luna gazed curiously at him.

"Any way," Dudley said. "Listen … I think your class is beginning?"

"Goodbye, Dudley," Luna said, brightly.

"See you, Luna,"

"New girlfriend?" Ron teased.

Hermione gave him a punch in the arm. "Ron, don't!" she said, reproachfully. "Luna's a sweet girl. She just wanted to thank Dudley."

"Yeah, Luna's alright," Dudley confirmed. He turned to look at her as she entered the classroom. She was still on her own—it seemed she still didn't have any friends besides Ginny. "Bit weird, but she's always nice to me."