"I can make light."

"Yes, and that will bring back Raffmir and his sister back faster than anything else. Just get on with it, before they come back."

Reluctantly I sidled my way around to the gantry and then felt my way onto the slimy ladder. I climbed it looking upwards unable to tell whether anything lurked in the shadows above, waiting for me to poke my head over. Thankfully nothing was.

I crossed the gantry carefully, as swiftly as I could, and lowered myself down the ladder on the other side. My descent was more elegant this time and I soon joined the dimly lit figure of Blackbird who had skipped lightly and lithely across the gaps below, belying her pensioner's appearance.

I joined her in the ring of torchlight and we made our way back along the ledge downstream. Once we were clear of the anvil hall the noise of the water diminished. "What did Raffmir mean about the barrier?" I asked Blackbird as she shifted our remaining torch between illuminating the path forward and making sure I didn't step on something slippery.

"I told you that the Untainted live in a world apart and they can cross into our world. You've seen that they can take over the body of someone gifted who is newly dead and also that they can also cross like Raffmir, as themselves. There was a time when they could only cross at certain times of the year, near the equinoxes or at a solstice, the times when things are balanced. "

"And now they cross all the time?"

"Not all the time, but their crossings have become more frequent and over a longer period."

"He said the barrier was weakening," I reminded her. "You know, it's strange. Kareesh taught me about the Feyre and about Fey history. It's not a written record like human history; it's wound up in stories of great deeds and terrible disasters the Feyre tell to their children and their grandchildren. She never mentioned a barrier against the Untainted, though. You'd think she would have done."

"A barrier would make sense. The Seventh Court take themselves off to their other world and the rest of the Feyre bolt the door after them."

"So where are the tales of this deed?" she asked. "Where are the names of those powerful enough to seal the gap between the worlds? It must have taken the combined efforts of more than one court, perhaps even all of them, to create a barrier that would withstand the Seventh Court. You'd think they would be proud of such an achievement."

She held the torch steady for me while I edged past the weir.

"Maybe it wasn't the Feyre that did it," I suggested. "You said hazel and iron were both symbolic for the Feyre. Maybe the Quit Rents Ceremony has something to do with it? Maybe it was humanity that sealed the barrier against the Seventh Court?"

"No, that's a human tradition. Humanity doesn't have any magic of its own, unless..."

"What?"

"They wouldn't have, would they?

"Wouldn't what?"

"What if the Six Courts cheated?"

"What do you mean?"

"What do the Six Courts have that the Seventh doesn't? What's the difference between them? "

"Humanity, I guess. The Seventh Court doesn't have anything to do with humans. "

"Precisely!"

We reached the stairway up to the access door and began climbing the steps up to the surface. We emerged into daylight and walked down to the pool in the open courtyard so we could wash our hands. I dipped them into the chilly water and scrubbed them together to remove the slimy residue. A curious goldfish came to investigate the cloudy water, and then flicked its tail and vanished as soon as it came near the discoloured water from my hands.

"So the Six Courts have humans and the Seventh doesn't. So what?"

"The Six Courts knew any barrier made by them could eventually be undermined by the Seventh. A barrier made with Fey magic could be broken with Fey magic. "

"So they got their humans to do it?"

"Perhaps initially, yes. They made the barrier, symbolised by hazel and iron and sealed it in an annual rite so it would be continually reinforced. Then they got humanity to carry out the ritual for them, so none of the Courts could break it."

"That works for the Feyre, but why would humanity take on such a duty? From their point of view, one lot of Feyre are as bad as another. Why would they take sides? Better to let them all kill each other. "

"Hmm, you're right. What's in it for them? Still, if the barrier fails then we're all in trouble. You heard Raffmir's sister. Once the barrier comes down she and her friends intend to feed and I'm guessing it won't just be other Feyre they're preying on."

"Well, for the moment we have the advantage that we know what they're up to."

"That's just it, though. We don't, do we? All we know is that Raffmir said there is a worm at the heart of the ritual and the barrier will fail because of it. If the ritual is the Quit Rents Ceremony then what's wrong with it? You said they're still doing it, even after all this time. So where's the worm?"

"We have to speak to the Queen's Remembrancer. Maybe he will know what's wrong with it?" I glanced at my watch. "It's gone two o'clock. We could go back and talk to the nice receptionist. She was going to check the dates of the ceremony, so maybe we can turn that into an introduction?"

I shook the remaining water from my hands and Blackbird and I wound our way back through the alleys and courtyards to the Strand and the Royal Courts of Justice.

I was more confident about approaching the security station this time, now that I had managed to maintain my glamour for a while. Blackbird was right, after a time you got used to it and didn't give it a thought. I emptied my pockets into the trays for the scanner and went through the metal detectors.

"Let me handle this," I suggested to Blackbird.

She gave me a sceptical look, but conceded. I moved up to the reception desk where the same lady was typing at her computer. She looked up as I approached the desk.

"Hi, honey, did you want me to find out those dates for you now?"

"Actually, I was wondering whether it would be possible to have a chat with the Queen's Remembrancer. "

"You want to make an appointment?" She reached for the telephone.

"Well, we were really just hoping for a quick word, if he or she is available."

"He's usually quite booked up, I'm afraid. The Remembrancer is only a ceremonial role and his other duties take up most of his time. Would you like me to talk to his clerk and see if he can slot you in later in the week? "

"Hmmm. Not really. It's kind of urgent, in a historical way. Is there any possibility you could have a word with his clerk and see if we could have five or ten minutes now? I would really appreciate it."

She peered at me over her gla.s.ses. "This is highly irregular, but I suppose there's no harm in asking. Who shall I say wants to see him?"

I realised I was going to have to give my name and we were still only ten feet from the security station where the guards were scanning the belongings of people returning from lunch. "It's Niall... Niall Dobson." I borrowed my ex-wife's surname in a moment of inspiration, "and this is my friend..." I ran out of steam as I realised the only name I had for my companion wouldn't do for this occasion either.

"Veronica." Blackbird stepped forwards. "Doctor Veronica Delemere. I'm with the University of London at Birkbeck."

I glanced sideways at Blackbird and then back to the receptionist, who gave me a look that said she wasn't impressed by University types. Nevertheless she picked up the phone and dialled a rapid sequence of digits. "Claire? Claire, it's Marcie. I have a couple of visitors who would like to speak with the Queen's Remembrancer about his duties. One of them is from Birkbeck and the other is from...?" She looked up at me. "I'm just an interested amateur," I demurred.

"He says he's an amateur, but he's very charming." She smiled at me in a conspiratorial way. "Yes, I know he's busy, but they only want fifteen minutes and they say it's urgent." She paused to listen.

"I know, I know, but they just wondered if he would meet them. They claim it's about something historically interesting. Ten minutes would do? You know how he is about his history." There was a pause. "Sure, I'll wait." She whispered to me. "She's just checking."

"We really are very grateful for your help."

"Oh, that's OK. He loves historical things, especially if there's a mystery. There is a mystery, isn't there? "

"Oh yes," I nodded. "It's a mystery all right." I glanced at Blackbird.

Marcie's attention was drawn back to the phone.

"That's great. I'll send them up." She put the phone back on the cradle. "She says you can go on up now. Just don't try and sell him something or you'll get me in a world of trouble. You see that balcony there and the archway below it? Go up the stairway and turn to your right at the top. Go down the corridor and Claire will be waiting for you. Don't get lost. "