why."

"But you've known so many men," I said.

"Oh yes," said Pretty Poison. "You have no idea how many, and none of them ever meant a damned thing to me. They said they loved me, here on Earth, but down in the sunless lands they all sang a different tune. They would have betrayed me a hundred times over, for just one more moment of life and light. I never mattered a damn to any of them. Sidney ... is different."

"Pretty Poison was the only one of her kind not to take part in the recent angel war over the Nightside," Sinner said mildly. "Because I asked her not to. Make of that what you will. Now, word travels quickly in the Nightside. And the word is, you've been hired to investigate the true beginnings of the Nightside. By no less a Being than the mercurial Lady Luck herself. You do mix with the most interesting people, John. I have to say, the true nature and purpose of the Nightside is a mystery that has long fascinated me. Do I take it you wish me to accompany you on this most dangerous of quests?"

"Got it in one," I said. "With you and Madman as human shields, I might get through this case alive after all. If I can drag you away from your vital researches, of course..."

Sinner closed the Bible and drummed his fingers on the cover. "My only hope of ever getting into Heaven lies in doing good deeds," he said flatly. "And I mean really impressive, major good deeds. I think keeping you alive in the face of all the really nasty Powers and Dominations who will undoubtedly try to kill you should qualify as good deeds above and beyond the call of duty."

"But what about me, Sidney?" said Pretty Poison. "You wouldn't leave me behind, would you? You know we can only be together forever in Hell."

Sinner smiled, and patted her hand fondly. "I wouldn't go to Heaven without you. Because if you weren't there, it wouldn't be Heaven."

"Dear Sidney." She leaned over, kissed him on the forehead, and tousled his hair with a lazy finger.

Sinner fixed me with a firm stare. "If I go with you on your quest, Pretty Poison comes with me. I will not be parted from her."

"Hell, I'm bringing Madman," I said. "The more firepower, the better."

"I heard that," said Madman, from deep in the stacks. "I am not firepower. I am a deterrent."

"The truth concerning the origins of the Nightside is long buried," Sinner said thoughtfully. "Probably with good cause. It stands to reason that an appalling place like this would have a truly awful beginning. The roots of the Nightside are almost certainly soaked in blood and suffering. You must understand, John—should the secrets we discover pose a threat to the safety and stability of the people of the Nightside, I could not allow them to be made public. Above all, I always strive to do no harm. Is this an acceptable condition to you?"

"Of course," I said. "I only report to my client, in this case Lady Luck. What she might do with the information afterwards is something you and she would have to sort out between you. Is that acceptable to you?"

He nodded, and we all smiled at each other in a very civilised way. Behind the smiles, I was quietly seething. Having Pretty Poison along struck me as a really bad idea. Things were going to be complicated enough without having a demon succubus from Hell peering over my shoulder. (Assuming I ever was stupid enough to turn my back on her.) But it was clear her presence was a deal-breaker for Sinner, so I had no choice but to agree, for now. Maybe we could use her for defusing booby-traps.

"Oh dear," Sinner said abruptly, rising to his feet. "I do believe something bad is about to happen."

I looked quickly about me. "What makes you say that?"

"Because Madman's music has just got all tense and dramatic."

He was right. It had. And thirteen men in smart city suits were strolling arrogantly through the Library stacks towards us. A Devil's Dozen of proud, purposeful-looking men, all of them heading straight for me. The few remaining scholars were gathering up their papers and fading away into the surrounding stacks with remarkably speed and dexterity. Even the Library staff were making themselves scarce. They didn't want anything to do with what was about to happen, and I didn't blame them. I knew