So Voldemort had managed to wheedle the location of the lost diadem out of the Gray Lady. He had traveled to that far-flung forest and retrieved the diadem from its hiding place, perhaps as soon as he left Hogwarts, before he even started work at Borgin and Burkes.
And wouldn’t those secluded Albanian woods have seemed an excellent refuge when, so much later, Voldemort had needed a place to lie low, undisturbed, for ten long years?
But the diadem, once it became his precious Horcrux, had not been left in that lowly tree. . . . No, the diadem had been returned secretly to its true home, and Voldemort must have put it there —
“— the night he asked for a job!” said Harry, finishing his thought.
“I beg your pardon?”
“He hid the diadem in the castle, the night he asked Dumbledore to let him teach!” said Harry. Saying it out loud enabled him to make sense of it all. “He must’ve hidden the diadem on his way up to, or down from, Dumbledore’s office! But it was still worth trying to get the job — then he might’ve got the chance to nick Gryffindor’s sword as well — thank you, thanks!”
Harry left her floating there, looking utterly bewildered. As he rounded the corner back into the entrance hall, he checked his watch. It was five minutes until midnight, and though he now knew what the last Horcrux was, he was no closer to discovering where it was. . . .
Generations of students had failed to find the diadem; that suggested that it was not in Ravenclaw Tower — but if not there, where? What hiding place had Tom Riddle discovered inside Hogwarts Castle, that he believed would remain secret forever?
Lost in desperate speculation, Harry turned a corner, but he had taken only a few steps down the new corridor when the window to his left broke open with a deafening, shattering crash. As he leapt aside, a gigantic body flew in through the window and hit the opposite wall. Something large and furry detached itself, whimpering, from the new arrival and flung itself at Harry.
“Hagrid!” Harry bellowed, fighting off Fang the boarhound’s attentions as the enormous bearded figure clambered to his feet. “What the — ?”
“Harry, yer here! Yer here!”
Hagrid stooped down, bestowed upon Harry a cursory and rib-cracking hug, then ran back to the shattered window.
“Good boy, Grawpy!” he bellowed through the hole in the window. “I’ll see yer in a moment, there’s a good lad!”
Beyond Hagrid, out in the dark night, Harry saw bursts of light in the distance and heard a weird, keening scream. He looked down at his watch: It was midnight. The battle had begun.
“Blimey, Harry,” panted Hagrid, “this is it, eh? Time ter fight?”
“Hagrid, where have you come from?”
“Heard You-Know-Who from up in our cave,” said Hagrid grimly. “Voice carried, didn’ it? ‘Yeh got till midnight ter gimme Potter.’ Knew yeh mus’ be here, knew what mus’ be happenin’. Get down, Fang. So we come ter join in, me an’ Grawpy an’ Fang. Smashed our way through the boundary by the forest, Grawpy was carryin’ us, Fang an’ me. Told him ter let me down at the castle, so he shoved me through the window, bless him. Not exac’ly what I meant, bu’ — where’s Ron an’ Hermione?”
“That,” said Harry, “is a really good question. Come on.”
They hurried together along the corridor, Fang lolloping beside them. Harry could hear movement through the corridors all around: running footsteps, shouts; through the windows, he could see more flashes of light in the dark grounds.
“Where’re we goin’?” puffed Hagrid, pounding along at Harry’s heels, making the floorboards quake.
“I dunno exactly,” said Harry, making another random turn, “but Ron and Hermione must be around here somewhere. . . .”
The first casualties of the battle were already strewn across the passage ahead: The two stone gargoyles that usually guarded the entrance to the staffroom had been smashed apart by a jinx that had sailed through another broken window. Their remains stirred feebly on the floor, and as Harry leapt over one of their disembodied heads, it moaned faintly, “Oh, don’t mind me . . . I’ll just lie here and crumble. . . .”
Its ugly stone face made Harry think suddenly of the marble bust of Rowena Ravenclaw at Xenophilius’s house, wearing that mad headdress — and then of the statue in Ravenclaw Tower, with the stone diadem upon her white curls. . . .
And as he reached the end of the passage, the memory of a third stone effigy came back to him: that of an ugly old warlock, onto whose head Harry himself had placed a wig and a battered old tiara. The shock shot through Harry with the heat of firewhisky, and he nearly stumbled.
He knew, at last, where the Horcrux sat waiting for him. . . .
Tom Riddle, who confided in no one and operated alone, might have been arrogant enough to assume that he, and only he, had penetrated the deepest mysteries of Hogwarts Castle. Of course, Dumbledore and Flitwick, those model pupils, had never set foot in that particular place, but he, Harry, had strayed off the beaten track in his time at school — here at last was a secret he and Voldemort knew, that Dumbledore had never discovered —
He was roused by Professor Sprout, who was thundering past followed by Neville and half a dozen others, all of them wearing earmuffs and carrying what appeared to be large potted plants.
“Mandrakes!” Neville bellowed at Harry over his shoulder as he ran. “Going to lob them over the walls — they won’t like this!”