"Malfoy!" cried Ron.
Draco threw back the hood of his cloak and collapsed to the ground, laughing.
"I wish I could have seen the looks on your faces…"
Ron swore loudly and Hermione hastily tried to shush both of them.
"What the bloody hell do you think you're doing?!" hissed Ron. "You know it's probably the night Potter's gonna come and you're wandering around in broad daylight…well, you know what I mean, as visible as you please…"
"Calm down, Weasley," said Draco, wiping his eyes. "I thought about what Granger said about it making more sense to have two up with Snape guarding It, as he's so incompetent…"
"That's not what I said, and anyway, I changed my mind. Ron needs to be here with me."
"All right, so give me some of that potion and I'll go stand guard at Gryffindor Tower or something."
"You don't even know where that is," said Ron, "and we haven't got any extra."
"Yes I do, I followed you, more than once, and I bet my life Granger the über-prepared has some extra."
A small green vial appeared, floating in the air.
"Ever since that night you didn't bring enough, Ron," she explained as Malfoy grabbed it. "There are about eight doses in there. Should see you through till morning, anyway."
"Good, well, I'll just…what was that?"
It seemed to them all for a moment that a shadow at the other end of the corridor had moved. Draco doused his cloak in Potion and flung it over his head, and for the space or thirty seconds there was complete silence in the corridor. The children strained their eyes and ears to detect any movement or sound, any breath or vibration.
"You'd better head on up, Malfoy," whispered Ron.
There was no answer.
The bearded head of the Potions Master, Arbutus, peered down at Harry, eyes glittering behind his glasses.
"You!" said Harry, sitting bolt upright. "What are you doing here?" For a moment he wondered if he could have been all wrong, if he could have misinterpreted everything that had happened…
"Trying to save your life, Snape," said Arbutus, throwing the curtains back properly. "Hurry, get up, you've got to get out of here, you're in terrible danger."
"I know I'm in danger, I'm ready for him. I'll…"
"You'll what? Face him down? In here? With all your little friends just waiting to be collateral damage? No, you have to get out. Come with me, now."
"Why should I? How do I know I can trust you? How do I know you're not working for him?"
"There's no time, Snape!"
"You...you won't take Harry," stammered Neville's voice. Harry and Arbutus both looked up to see Nevile standing beside his bed, shaking like a leaf, but pointing his wand straight at Arbutus's head. "I'll fight you."
Arbutus made a funny growling sound in the back of his throat and wheeled back around to face Harry, who had taken the opportunity to seize his own wand.
"Just give me one reason to trust you," he said, trying to sound nonchalant, like a hero in an action movie.
"That recipe," said Arbutus. "That potion. Who did you think sent it to you?"
Harry stared. "I thought…Professor Dumbledore, or maybe Professor McGonagall…"
"Stupid boy, a potion and you never thought of the Potions Master?"
"You…?"
"Your father trusted me. Is that enough for you?"
"How do I know you didn't just, just steal it or something?"
"And give it right back to you? Why would I bother?"
He and Harry looked at each other for a long moment. Harry couldn't think of an answer.
"If I did go with you, where would you be taking me?" he asked eventually.
"Somewhere safe, I hope."
"You hope?"
"Hurry. Bring your wand."
"Go out ahead of me. I'll be right behind you."
Arbutus peered at him swiftly and then nodded and left the room. Harry dug under his pillow for the jar.
"Wh-what's that?" asked Neville, who was now trembling with relief at not having had his head blown off.
"Nothing, Neville. Go to sleep. Or at least close your eyes."
He pulled his bedclothes up over his pillow and bunched them up a little to look, in the dim light at least, like there was someone there, and then he drew the curtains closed and hefted the jar in his hands. He looked around the room quickly.
Arbutus wasn't very good at being stealthy. At his recommendation, Harry had dosed himself with the Potion, but Arbutus just walked down the corridors, not bothering to muffle his footsteps or look for someone coming or anything. Harry supposed no one was after him.
They zigged and zagged until Harry wasn't sure where they were anymore. He was beginning to recognise the sensation of being completely and utterly lost in the labyrinthine castle, and the sensation of mortal terror wasn't anything new to him either.
"Almost there, Snape," said Arbutus, turning around to look at Harry. "You just have to…oi!" Suddenly he tensed and seized his wand. Not quickly enough.
"Stupefy!" shouted a voice. A jet of bright red light shot past Harry and slammed into the professor; he crumpled to the ground.
Oh, perfect, thought Harry.
He stood staring at the fallen Potions Master. If he was very, very still, if he didn't make a noise or breathe or move a muscle, maybe Potter wouldn't be able to get at him. Then again, if Dumbledore could see him then why not Potter…?
He heard a low chuckle behind him and frowned. That didn't sound like Potter…
"Come out, come out, wherever you are," said the voice. Definitely not Potter. But it didn't sound like anyone else he knew either. He heard slow footsteps behind him, drawing nearer. He could imagine hands groping in the air, coming up behind him, lighting on him any second.
"I know you're there," said the voice. No, it did sound slightly familiar, but wrong, somehow, as if something was missing. "Why don't you make this easier for everyone, Snape? Just tell me where the Stone is and I'll kill you fairly painlessly."
It was like seeing a film star and trying to remember what else you'd seen them in, only this time they're playing an alien or something, and you have to kind of look at the face behind the make-up…
"On the other hand, if I find you now, it's going to be extremely painful. And then I'm still going to get the Stone. So why bother keeping it from me now?"
If he could just distract whoever-it-was for a second. Were there any invisible spells, anything that would make something move in another part of the corridor, just so he could get out of the path, hide behind something, do the Amplifying charm, something? Or could he try that stupefying spell…no, he didn't know how…or what about Protego Maxima? That would give away his position…how long had it been, anyway? The Potion would wear off eventually even if whoever-it-was didn't find him right away…
Throw something. Make a noise far enough away from himself that it would be a distraction. He reached in his pocket and his fingers closed around a small cut stone…
The suit of armour clanged loudly and toppled as the stone hit it. Harry took a chance and ran while the armour was still reverberating, and ducked behind a statue. He heard a curse behind him and saw a flash of bright light fly past his hiding spot; when it exploded, he cast the Amplifying charm on his throat as quickly and quietly as possible.
"Amplifying charm," said George. "Piece of cake."
"But that's no good, the whole world'd be able to hear you," said Ron.
"See, the brilliant thing about this spell, Ronniekins," said Fred, "is it not only makes it impossible for anyone not to listen to you, it also makes it impossible for them to tell where you are by your voice. You echo all over the place, see? You fill the space with your voice. You're everywhere and nowhere…"
"They'd triangulate eventually," said Hermione, turning a page. "And they'd always be able to recognise your voice."
"Sure," said George. "But it buys you a bit of time, doesn't it? Anyway, it's ten to one he'll know it's us already..."
Harry waited, trying not to breathe. From where he stood he could see the corridor with one eye; for a few minutes, nothing happened, and then a dark shape moved in front of him, prowling just like he'd imagined, blindly groping to catch the invisible opponent...
The shape passed a window on the other side of the hall. There wasn't much light, but Harry could just see the face.