As Hermione came flying out of the cave, moving so fast that her feet hardly seemed to touch the ground, Harry bolted upright, wand at the ready. "What is it?" he demanded. "What happened? What was the test? What happened?"

"It... it was me," she panted, stumbling to a halt and tugging at Harry's elbow. "The ghost. At first I couldn't see her face, and she said I had to get past her, and - will you come on?"

Harry sighed and allowed himself to be led out of the woods before he stopped and repeated, "So what happened?"

"Well, when she turned around to face me, I could see she was wearing a mask like the ones they used to wear-"

"May I assume that 'they' means the Death Eaters?"

"Of course it does, who else do you know that wears masks?" Hermione said furiously. "Now do you want to hear this, or not? She was wearing a mask just like those ones, and so I thought, all right, it's a duel, I dueled loads of Death Eaters in the War, I can handle this - do you think we should get a little further away?"

"If you want to."

"Good. I do." She marched the two of them some distance further on, stopping on the other side of a large stone that would hide them from any watchers in the fringes of the forest, and went on, "So I cast a few curses - oh, don't look so worried, I didn't use anything serious - but she didn't fight back, just fell over, and the mask just sort of faded away and it was me underneath!"

Harry blinked owlishly at her. "Er... not to make light of the situation, but you haven't been watching Muggle films lately, have you?"

"I know." Hermione sat down on the grass, leaning against the stone, and beckoned him down to join her. "I've got a theory about that, though. I think they can only work with what's already in your head. I must have watched Star Wars a million times, I know that scene backwards and forwards, and walking into a dark cave to face a mysterious enemy - the comparison occurred to me. And the - the ghosts, I suppose - I don't think they're ghosts at all, but anyway, they pick up what you're thinking, and they use it. Except she couldn't actually look like Darth Vader, because she knew I'd think that was ridiculous, but - well, look, anyway, that's not important. The thing is, they know what we're thinking."

"Well, yeah. I mean, they know what we're afraid of, anyway. Otherwise Neville wouldn't have seen that toy monkey of his." Harry shrugged. "That's important?"

"Of course it's important!" She looked at him crossly. "Look, think of it this way. Taking the test shows them how to get into your head. Before that, they can't go very deep, but once you've taken the test, they can get into your subconscious. Bill doesn't think he controls them, but he does! It's his subconscious mind! Harry, we have to get out of here!"

Harry sighed. "I know we have to get out of here, all right? But we have to get Ginny and Bill out of here, too. No, don't start going on about leaving Bill, there's not time for an argument right now - he didn't mean to hurt anybody, and I'm not leaving him here to be torn to bits by these things. We'll fetch the two of them, we'll leave, and we'll tell Dumbledore to leave the wards up to keep anyone else from wandering in here and getting on the bad side of those ghosts. Come on."