“No, of course I didn’t,” said Harry quickly. “Dobby, you can sleep, all right? But has either of you found out anything?” he hastened to ask, before Hermione could intervene again.
“Master Malfoy moves with a nobility that befits his pure blood,” croaked Kreacher at once. “His features recall the fine bones of my mistress and his manners are those of —”
“Draco Malfoy is a bad boy!” squeaked Dobby angrily. “A bad boy who — who —”
He shuddered from the tassel of his tea cozy to the toes of his socks and then ran at the fire, as though about to dive into it; Harry, to whom this was not entirely unexpected, caught him around the middle and held him fast. For a few seconds Dobby struggled, then went limp.
“Thank you, Harry Potter,” he panted. “Dobby still finds it difficult to speak ill of his old masters. . . .”
Harry released him; Dobby straightened his tea cozy and said defiantly to Kreacher, “But Kreacher should know that Draco Malfoy is not a good master to a house-elf!”
“Yeah, we don’t need to hear about you being in love with Malfoy,” Harry told Kreacher. “Let’s fast forward to where he’s actually been going.”
Kreacher bowed again, looking furious, and then said, “Master Malfoy eats in the Great Hall, he sleeps in a dormitory in the dungeons, he attends his classes in a variety of —”
“Dobby, you tell me,” said Harry, cutting across Kreacher. “Has he been going anywhere he shouldn’t have?”
“Harry Potter, sir,” squeaked Dobby, his great orblike eyes shining in the firelight, “the Malfoy boy is breaking no rules that Dobby can discover, but he is still keen to avoid detection. He has been making regular visits to the seventh floor with a variety of other students, who keep watch for him while he enters —”
“The Room of Requirement!” said Harry, smacking himself hard on the forehead with Advanced Potion-Making. Hermione and Ron stared at him. “That’s where he’s been sneaking off to! That’s where he’s doing . . . whatever he’s doing! And I bet that’s why he’s been disappearing off the map — come to think of it, I’ve never seen the Room of Requirement on there!”
“Maybe the Marauders never knew the room was there,” said Ron.
“I think it’ll be part of the magic of the room,” said Hermione. “If you need it to be Unplottable, it will be.”
“Dobby, have you managed to get in to have a look at what Malfoy’s doing?” said Harry eagerly.
“No, Harry Potter, that is impossible,” said Dobby.
“No, it’s not,” said Harry at once. “Malfoy got into our headquarters there last year, so I’ll be able to get in and spy on him, no problem.”
“But I don’t think you will, Harry,” said Hermione slowly. “Malfoy already knew exactly how we were using the room, didn’t he, because that stupid Marietta had blabbed. He needed the room to become the headquarters of the D.A., so it did. But you don’t know what the room becomes when Malfoy goes in there, so you don’t know what to ask it to transform into.”
“There’ll be a way around that,” said Harry dismissively. “You’ve done brilliantly, Dobby.”
“Kreacher’s done well too,” said Hermione kindly; but far from looking grateful, Kreacher averted his huge, bloodshot eyes and croaked at the ceiling, “The Mudblood is speaking to Kreacher, Kreacher will pretend he cannot hear —”
“Get out of it,” Harry snapped at him, and Kreacher made one last deep bow and Disapparated. “You’d better go and get some sleep too, Dobby.”
“Thank you, Harry Potter, sir!” squeaked Dobby happily, and he too vanished.
“How good’s this?” said Harry enthusiastically, turning to Ron and Hermione the moment the room was elf-free again. “We know where Malfoy’s going! We’ve got him cornered now!”
“Yeah, it’s great,” said Ron glumly, who was attempting to mop up the sodden mass of ink that had recently been an almost completed essay. Hermione pulled it toward her and began siphoning the ink off with her wand.
“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. “It’s 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 Slughorn 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 come 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. . . .”