“But what’s all this about him going up there with a variety of students‘?” said Hermione. “How many people are in on it? You wouldn’t think he’d trust lots of them to know what he’s doing-”

“Yeah, that is weird,” said Harry, frowning. “I heard him telling Crabbe it wasn’t Crabbe’s business what he was doing… so what’s he telling all these… all these…” Harry’s voice tailed away; he was staring at the fire. “God, I’ve been stupid,” he said quietly. “Its obvious, isn’t it? There was a great vat of it down in the dungeon… He could’ve nicked some any time during that lesson…”

“Nicked what?” said Ron.

“Polyjuice Potion. He stole some of the Polyjuice Potion Slug-horn showed us in our first Potions lesson… There aren’t a whole variety of students standing guard for Malfoy… it’s just Crabbe and Goyle as usual. …Yeah, it all fits!” said Harry, jumping up and starting to pace in front of the fire. “They’re stupid enough to do what they’re told even if he won’t tell them what he’s up to, but he doesn’t want them to be seen lurking around outside the Room of Requirement, so he’s got them taking Polyjuice to make them look like other people… Those two girls I saw him with when he missed Quidditch — ha! Crabbe and Goyle!”

“Do you mean to say,” said Hermione in a hushed voice, “that that little girl whose scales I repaired — ?”

“Yeah, of course!” said Harry loudly, staring at her. “Of course! Malfoy must’ve been inside the room at the time, so she — what am I talking about? — he dropped the scales to tell Malfoy not to corne out, because there was someone there! And there was that girl who dropped the toadspawn too! We’ve been walking past him all the time and not realizing it!”

“He’s got Crabbe and Goyle transforming into girls?” guffawed Ron. “Blimey… no wonder they don’t look too happy these days. I’m surprised they don’t tell him to stuff it.”

“Well, they wouldn’t, would they, if he’s shown them his Dark Mark?” said Harry.

“Hmmm… the Dark Mark we don’t know exists,” said Hermione skeptically, rolling up Ron’s dried essay before it could come to any more harm and handing it to him.

“We’ll see” said Harry confidently.

“Yes, we will,” Hermione said, getting to her feet and stretching. “But, Harry, before you get all excited, I still don’t think you’ll be able to get into the Room of Requirement without knowing what’s there first‘. And I don’t think you should forget” — she heaved her bag onto her shoulder and gave him a very serious look — “that what you’re supposed to be concentrating on is getting that memory from Slughorn. Good night.”

Harry watched her go, feeling slightly disgruntled. Once the door to the girls’ dormitories had closed behind her he rounded on Ron. “What d’you think?”

“Wish I could Disapparate like a house-elf,” said Ron, staring at the spot where Dobby had vanished. “I’d have that Apparition Test in the bag.”

Harry did not sleep well that night. He lay awake for what felt like hours, wondering how Malfoy was using the Room of Requirement and what he, Harry, would see when he went in there the following day, for whatever Hermione said, Harry was sure that if Malfoy had-=— been able to see the headquarters of the D.A., he would be able to see Malfoy’s, what could it be? A meeting place? A hideout? A ston room? A workshop? Harrys mind worked feverishly and his dreams, when he finally fell asleep, were broken and disturbed by images of Malfoy, who turned into Slughorn, who turned into Snape…

Harry was in a state of great anticipation over breakfast the following morning; he had a free period before Defense Against the Dark Arts and was determined to spend it trying to get into the Room of Requirement. Hermione was rather ostentatiously showing no interest in his whispered plans for forcing entry into the room, which irritated Harry, because he thought she might be a lot of help if she wanted to.

“Look,” he said quietly, leaning forward and putting a hand on the Daily Prophet, which she had just removed from a post owl, to stop her from opening it and vanishing behind it. “I haven’t forgotten about Slughorn, but I haven’t got a clue how to get that memory off him, and until I get a brain wave why shouldn’t I find out what Malfoy’s doing?”

“I’ve already told you, you need to persuade Slughorn,” said Hermione. “It’s not a question of tricking him or bewitching him, or Dumbledore could have done it in a second. Instead of messing around outside the Room of Requirement” — she jerked the Prophet out from under Harrys hand and unfolded it to look at the front page — “you should go and find Slughorn and start appealing to his better nature.”

“Anyone we know — ?” asked Ron, as Hermione scanned the headlines.

“Yes!” said Hermione, causing both Harry and Ron to gag on their breakfast. “But it’s all right, he’s not dead — its Mundungus, he’s been arrested and sent to Azkaban! Something to do with impersonating an Inferius during an attempted burglary, and someone called Octavius Pepper has vanished. Oh, and how horrible, a nine-year-old boy has been arrested for trying to kill his grandparents, they think he was under the Imperius Curse.”

They finished their breakfast in silence. Hermione set off immediately for Ancient Runes; Ron for the common room, where he still had to finish his conclusion on Snape’s dementor essay, and Harry for the corridor on the seventh floor and the stretch of wall opposite the tapestry of Barnabas the Barmy teaching trolls to do ballet.

Harry slipped on his Invisibility Cloak once he had found an empty passage, but he need not have bothered. When he reached his destination he found it deserted. Harry was not sure whether his chances of getting inside the room were better with Malfoy inside it or out, but at least his first attempt was not going to be complicated by the presence of Crabbe or Goyle pretending to be an eleven-year-old girl.

He closed his eyes as he approached the place where the Room of Requirement’s door was concealed. He knew what he had to do; he had become most accomplished at it last year. Concentrating with all his might he thought, “I need to see what Malfoy’s doing in here… I need to see what Malfoy’s doing in here… I need to see what Malfoy’s doing in here…”

Three times he walked past the door; then, his heart pounding with excitement, he opened his eyes and faced it — but he was still looking at a stretch of mundanely blank wall. He moved forward and gave it an experimental push. The stone remained solid and unyielding.

“Okay,” said Harry aloud. “Okay… I thought the wrong thing…” He pondered for a moment then set off again, eyes closed, concentrating as hard as he could. “I need to see the place where Malfoy keeps coming secretly… I need to see the place where Malfoy keeps coming secretly…” After three walks past, he opened his eyes expectantly.

There was no door.

“Oh, come off it,” he told the wall irritably. “That was a clear instruction. Fine.” He thought hard for several minutes before striding off once more. “I need you to become the place you become for Draco Malfoy…”

He did not immediately open his eyes when he had finished his patrolling; he was listening hard, as though he might hear the door pop into existence. He heard nothing, however, except the distant twittering of birds outside. He opened his eyes.

There was still no door.

Harry swore. Someone screamed. He looked around to see a gaggle of first years running back around the corner, apparently under the impression that they had just encountered a particularly foulmouthed ghost.

Harry tried every variation of “I need to see what Draco Malfoy is doing inside you” that he could think of for a whole hour, at the end of which he was forced to concede that Hermione might have had a point: The room simply did not want to open for him. Frustrated and annoyed, he set off for Defense Against the Dark Arts, pulling off his Invisibility Cloak and stuffing it into his bag as he went.

“Late again, Potter,” said Snape coldly, as Harry hurried into the candlelit classroom. “Ten points from Gryfrindor.” Harry scowled at Snape as he flung himself into the seat beside Ron. Half the class were still on their feet, taking out books and organizing their things; he could not be much later than any of them.

“Before we start, I want your dementor essays,” said Snape, waving his wand carelessly, so that twenty-five scrolls of parchment soared into the air and landed in a neat pile on his desk. “And I hope for your sakes they are better than the tripe I had to endure on resisting the Imperius Curse. Now, if you will all open your books to page — what is it, Mr. Finnigan?”

“Sir,” said Seamus, “I’ve been wondering, how do you tell the difference between an Inferius and a ghost? Because there was something in the paper about an Inferius —”

“No, there wasn’t,” said Snape in a bored voice.

“But sir, I heard people talking —”

“If you had actually read the article in question, Mr. Finnigan, you would have known that the so-called Inferius was nothing but a smelly sneak thief by the name of Mundungus Fletcher.”

“I thought Snape and Mundungus were on the same side,” muttered Harry to Ron and Hermione. “Shouldn’t he be upset Mundungus has been arrest —”

“But Potter seems to have a lot to say on the subject,” said Snape, pointing suddenly at the back of the room, his black eyes fixed on Harry. “Let us ask Potter how we would tell the difference between an Inferius and a ghost.”

The whole class looked around at Harry, who hastily tried to recall what Dumbledore had told him the night that they had gone to visit Slughorn. “Er — well — ghosts are transparent —” he said.

“Oh, very good,” interrupted Snape, his lip curling. “Yes, it in easy to see that nearly six years of magical education have not been wasted on you, Potter. ‘Ghosts are transparent.”’

Pansy Parkinson let out a high-pitched giggle. Several other people were smirking. Harry took a deep breath and continued calmly, though his insides were boiling, “Yeah, ghosts are transparent, but Inferi are dead bodies, aren’t they? So they’d be solid —”

“A five-year-old could have told us as much,” sneered Snape. “The Inferius is a corpse that has been reanimated by a Dark wizard’s spells. It is not alive, it is merely used like a puppet to do the wizard’s bidding. A ghost, as I trust that you are all aware by now, is the imprint of a departed soul left upon the earth, and of course, as Potter so wisely tells us, transparent. ”