She was aware of its lulling music before anything else, the sound of water flowing over stone. Then she realised that her eyes were already open, that the pearly opalescent sheen over to one side was light flooding into a cave, that she was lying in it, with a blanket or some light bedspread over her, that she was - ouch! - one fiery mass of aches and pains.
She groaned, tried to roll over and saw - him.
He was an elderly man, wrapped in an offcolour robe. He looked a little like her image of Socrates or Plato or one of those Greek philosophers of the past: the robe, the bare shoulders, the comforting white beard.
"Where am I?" she managed, after a while.
He smiled. "I'm sure you know that the answer to that question would mean little to you right now. Suffice it to say that you're right here. That you're alive (just barely). Do you require anything further?"
"Just - water."
He gestured towards the cup beside her elbow. "Water's there. I suggest you get some rest. I'll be back to check on you in a while. For the moment, though, I have some things to do."
Phil tried to ease herself up and off the - surprisingly comfortable - pallet she was lying on. Then gave it up as a bad job, and fell back into sleep: a fitful sleep this time, broken by nightmares of long corridors in the dark, and grinning bloody men with cruel spikes.
"You say you were once one of them."
"Not really. I've always been aware that others could find their way down here. So many have tried! But these men were different. They had no interest in exploring the farthest caverns: torture and sex-magic were the whole of their world, and heaven help the poor innocents who fell into their hands!"
"Like me and Pat."
"Like you and your friend Pat. She's over there, by the way. I buried her by the landslip over there, where the permasol is softest."
He gestured across the expanse of the huge cavern. He and Phil were sitting by the banks of a broad sea, streaks and filaments of orange vegetation radiating out from their faint human warmth.
"So how do you live down here?"
"All that can be explained another day. For now, I need to know just how you found your way in here."
"That's just it. I don't know. I must have been half mad, because I was talking to her head, and she answered me back! I swear she did! She started the conversation, in fact."
"You think you were imagining it, but you weren't. The radiation down here can have strange effects. It's why I'm still alive, essentially unaged, in this hollow world of rock and water. It's why your wounds are healing up so fast."
"I know it's a lot to grasp, all at one time. And I'd better tell you now - there's no way out of here."
"But the men, the torturers ..."
"Yes, I told you I tried to infiltrate them - for a time. At first I thought they'd grasped the central fact of this place, understood the effects it could have on human beings. I thought they were killing people to bring them back ..."
"And were they?"
"No. But I had to walk among them, talk to them, to work that out. They torture to kill, and to indulge themselves. There's nothing deeper in what they do. No end to the itch they're scratching."
"And did you ..."
"Yes, I had to. Or else they would have captured me, and my head would have been grinning from a pole. Bu tafter that I realised I had to shut myself off from them ... If they found this place not even they could ignore its potentialities."
"Bringing things back to life?"
"A kind of life, yes - life insofar as pain can be suffered by such a being. Certainly it would have skin to scorch and orifices to penetrate."
"Then how did I ..."
"That's what I'd like to know. I found you inside my perimeter. That means there's some way in. I've been closing off all the paths for years, blocking them with landfalls, cave-ins - everything designed to look natural."
"So ... this isn't Paradise."
"No, no paradise, no Shangri-La. I'm not a wise philosopher - just a man, a very old man, kept in a kind of artificial stasis by the lifecycles of this planet. And - I'm very much afraid - so, now, are you."
"And we're alone here?"
"After a fashion. In my early days I adopted a few children."
"Children! Boys and girls?"
"Not as you know them. That's how I know the half-life this place gives. We could dig up your friend's head, for instance - could question it like an oracle. But it wouldn't be her, nor could it tell us anything new."
"Are they flesh and blood? Animals? Machines?"
"Some specimens of each kind. They won't bother us unless we provoke them. They mostly live on the far side of the lake. You'll get to know them all -- if you wish to, that is."
"What's your name?"
"My children call me Philemon. But in the outside world I used to be called Petrie."
"Like the explorer?"
"Like the scientist, I like to think."
"Are we safe here? Can they get at us?"
"I'd have said we were safe, three days ago. That's when I found you, over by the rockfall. But now that I know there's at least one way in left open, I have to find it, close it off."
"But ... we could find it ourselves, escape from here, go back to the city, to the domes."
"Is that what you want?"
"I want to see my daughter, find out if she's okay. I want to get back to my life."
"I'm sorry. I understand what you're saying, but you have to remember my life-force depends on this place. I can't ever leave. There's nothing for me outside."
"But there is for me!"
"Perhaps there still is. Perhaps the process hasn't gone too far in your case. It soon will, though. I had a companion when I first came here, all those years ago. But we spent too long exploring our new world. When he tried to leave he shrivelled into dust. I found his body and buried him. Flint, he was called."
"But ... why didn't you shrivel into dust? If you followed him out."
"He never drank the water or ate the weeds."
Suddenly something clicked into place. She saw the milky mildness of his deep-set eyes as they actually were: a mask for thick, impenetrable cataracts of scar-tissue.
“Yes, I fed you on them. I’m sorry. I want you to stay with me and be my wife."