Robby answered promptly when they knocked at the door the next morning. "Master is saying Robby is to let you and Miss Doctor Granger in today, Harry Potter!" he said. "Come in! Robby is making tea for his master's friends! Come in!"

"Thank you, Robby," Hermione said after a moment's hesitation, bending down so her face was level with the house-elf's and making deliberate eye contact as if to prove her sincerity. "Why don't you sit down and have a rest, and we'll pour our own tea?"

"No, Miss Doctor Granger!" Robby looked shocked. "Robby is serving the tea, and Miss Doctor Granger and Harry Potter is talking to Robby's master." The house-elf beamed. "Robby's tea is made just the way Miss Doctor Granger and Harry Potter is drinking it when Robby is serving tea before!"

"That's excellent, Robby, really," Harry said absently, stepping across the threshold. "Thanks a lot - ow, Hermione, what?"

She tugged on his wrist. "I... oh, I've just remembered something. Something, er, back at the camp. That I have to do."

"Something at the camp?" Harry turned to follow her, bewildered. "'Bye, Robby... I expect we'll be back again soon..."

As soon as they were well away from the house, just over the nearest hill, he dug in his heels and brought both of them to a stop. "D'you know you're the worst liar I've ever had the privilege to meet?" he asked, his tone conversational. "Honestly, what was that about?"

"Keep moving." She gave his wrist another sharp tug.

"The camp's the other way."

"We're not going to the camp." Hermione's voice was full of disdain. "Don't you ever listen to anything anyone says? If people like you paid closer attention to house-elves-"

"Do you think that, just this once, you could perhaps skip the house-elf manifesto and move straight to the point?"

She rolled her eyes at him. "If you'd paid closer attention, you'd have heard Robby say that Bill told him to let you and me in. Not Malfoy. And he's already got tea prepared the way you and I take it. Again, not Malfoy. And none of this strikes you as just the slightest bit suspicious?" She shook her head. "I'm sorry, you got to be a captain how, exactly?"

"Well, being the only one who could kill Voldemort may have had a bit to do with it," Harry said crossly. "I was listening. I just thought he'd probably had Robby out to look in on us last night. He's snuck up to our tents before without us noticing, you know. He could perfectly well have looked in and seen that Malfoy wasn't there."

Hermione shook her head vehemently. "I'm sure Bill has more control over the monsters than he's admitting. I don't think it's safe for us to go into the house. We need to get Ginny and go, as soon as we can."

"Well, how are we meant to get Ginny without going into the house?"

"We're going to the cave." Hermione began marching determinedly forward once more. "I'm going to take the test. And I'm going to pass it."

"Hermione!" Harry ran to catch up with her. "You can't-"

She glared at him. "I can. It's a test. I've never failed a test, and I won't fail this one."

They kept walking, in silence.

It was some ten minutes later, deep inside the woods, when Hermione stopped suddenly. "I think this is it," she said, her voice almost a whisper. "It's the only cave I've seen, and there aren't any more hills around here for one to be inside." She looked carefully at the curve of the low hilltop. "Does that look... natural?"

Harry gave it a cursory glance. "No."

"You didn't even look."

"You're about to go into a cave and face some mad ghosts who want to kill us, and you're worried about whether it's a natural feature? Hermione, is this really the time for geological inquiry?" He sighed and took a closer look. "Anyway, I was right the first time. It's too round to be natural. Someone built it. You know, I really don't think it's a good idea to go in there..."

"Nonsense." Before he could stop her, she was inside the cave - too far inside, in the darkness, to be seen from where he stood.