The back of Harry’s robes was damp. One of the jars behind him had broken when he fell against it; the pickled slimy thing within was swirling in its draining potion.
“Reparo,” hissed Snape, and the jar sealed itself at once. “Well, Potter… that was certainly an improvement…” Panting slightly, Snape straightened the Pensieve in which he had again stored some of his thoughts before starting the lesson, almost as though he was checking they were still there. “I don’t remember telling you to use a Shield Charm… but there is no doubt that it was effective…”
Harry did not speak; he felt that to say anything might be dangerous. He was sure he had just broken into Snape’s memories, that he had just seen scenes from Snape’s childhood. It was unnerving to think that the little boy who had been crying as he watched his parents shouting was actually standing in front of him with such loathing in his eyes.
“Let’s try again, shall we?” said Snape.
Harry felt a thrill of dread; he was about to pay for what had just happened, he was sure of it. They moved back into position with the desk between them, Harry feeling he was going to find it much harder to empty his mind this time.
“On the count of three, then,” said Snape, raising his wand once more. “One—two—”
Harry did not have time to gather himself together and attempt to clear his mind before Snape cried, “Legilimens!”
He was hurtling along the corridor towards the Department of Mysteries, past the blank stone walls, past the torches—the plain black door was growing ever larger; he was moving so fast he was going to collide with it, he was feet from it and again he could see that chink of faint blue light—
The door had flown open! He was through it at last, inside a black-walled, black-floored circular room lit with blue-flamed candles, and there were more doors all around him—he needed to go on—but which door ought he to take—?
“POTTER!”
Harry opened his eyes. He was flat on his back again with no memory of having got there; he was also panting as though he really had run the length of the Department of Mysteries corridor, really had sprinted through the black door and found the circular room.
“Explain yourself!” said Snape, who was standing over him, looking furious.
“I… dunno what happened,” said Harry truthfully, standing up. There was a lump on the back of his head from where he had hit the ground and he felt feverish. “I’ve never seen that before. I mean, I told you, I’ve dreamed about the door… but it’s never opened before—”