"What did you just do?"

Vidocq says, "We're going to the thirteenth floor."

"There is no thirteenth floor," says Allegra. "Look at the buttons. This building only has five floors. And if it had more, it wouldn't have a thirteenth floor. It's bad luck. No one would move in."

"If you say so," he says, and pulls out the stop button. The car begins to move down. It stops at the third floor.

"See? We're on three again." Then something moves by the home-decor shop.

The window where the porcelain cheetah stood just a minute earlier is dark and lit only by candlelight. The big window is caked with a century's worth of dust and impacted grime. In the cheetah's place is a bell jar at least six feet tall. There's a woman inside. She's transparent and drained of color, nearly black and white. Her hair and dress billow around her, blown by some invisible storm. She screams and claws at the glass walls of her prison. When she sees people getting off the elevator, she goes quiet and stares at us like a lion tracking a herd of zebra. A second later, she's pounding on the bell-jar glass again and showing yellow, sharklike teeth.

The interior of the shop is dark and crowded and has the musty smell of an attic that hasn't been opened in fifty years. A shadow moves out of the shadows. It's a man. He's small, round, and black. Not the way Allegra is black, but black like a raven or an abyss. He's wearing an expensive-looking silk robe and holding a brass telescope.

"I see you've met my Fury," he says. "She's a very recent acquisition from Greece. Of course, I've had all three Furies at one time or another, but never all at once. That would be a coup." I look back at the Fury and out the dirty window. Women in business clothes and men in suits and carrying attache cases pass, completely unaware of the Fury and the strange store.

"Nice to see you all," says Mr. Muninn. "I was beginning to think that you'd forgotten about me."

"Never, my friend," says Vidocq. He introduces Allegra and then me.

Muninn takes my hand and doesn't let go.

"I've heard a lot about you, my boy." He stares up at me like he's trying to see out the back of my head. "Interesting. I thought I might see bit more of the devil in you. Perhaps it's best for us all that I can't."

"Vidocq said that you might have work for us."

"That I do, my boy. I'm a trader and a businessman. Merchandise comes in and merchandise goes out. I'm busy, busy, constantly busy. There's always work here for those who want to work and to earn a decent wage."

"We were hoping for more than decent."

"Then we'll have to find something indecent for you to do."

"You have so many beautiful things," says Allegra, picking up what looks like a basketball-size pearl with a map of the world caved on it.

"These are just baubles, shiny things to bring in the curious. Come. Let me show you the real store."

He sets down the telescope on a table overflowing with pocket watches, an orrery with the wrong number of planets, and a box of glass eyes, some of which are larger than the palm of my hand.

Muninn takes us through a steel door marked emergency exit. Beyond the door, the walls are rough, chiseled stone, like we're in a cave cut into a mountain. There's a stone stairway that's so narrow at points that we have to walk down single file. And it's not a short walk.

The trick getting into and out of a place like this is memorizing landmarks. Anything will do. Anything you can remember. A loose stair. A breeze from a hole in the wall. A crack in the rock face that looks like a sheep blowing the eagle on the presidential seal.

If it's too dark, like it is on Muninn's stairs, you can always steal a handful of rare and ancient coins from a bowl in a guy's shop and drop them like bread crumbs all the way until you get where you're going.

The most important thing to know about caverns is to never go in one without having a pretty good idea of how to get out. And never let yourself be led into said cavern by a stranger who owns his own Fury. That last one isn't absolute. It's just a good rule of thumb. It also helps to have a friend vouch for the guy, which is the only reason I'm still stumbling down a set of crumbling stairs dropping doubloons and drachmas behind me.

Just before we hit the bottom of the stairs, I can see where we're headed. It's huge. Like Texas huge. I can see the cavern's ceiling, but not the far walls. There's a junkyard of old tables, cabinets, and shelves at the bottom of the stairs. About fifty yards beyond that is what looks like a stone labyrinth that twists, turns, and snakes away into the distance. Can't see the end of that, either. It's like standing on the beach at Santa Monica and trying to see to Japan.

"Where did all this come from?" I ask.

"Oh, here and there. You know how it is when you stay in one place too long. You tend to accumulate things."

Shelves, dressers, and old tables are piled with books, old photos, jewelry, furs, false teeth, pickled hearts, and what might be dinosaur bones. Those are the normal bits. Sticking up over the top of the labyrinth's walls are parts of drive-in movie screens, the masts and deck of an old sailing ship, a lighthouse, and strange carnivorous trees that snap at the flocks of birds circling the ceiling.

"How long have you been here?"

"Forever. I think. It's hard to be sure about these things, isn't it? I mean, one ice age looks pretty much like another. But I've been here a long time and that's why everyone comes to me. I have all the best things. For sale or for trade. Buyer's choice."

"That's why we're here. 1 used up some of Vidocq's Spiritus Dei and need to pay him back."

Muninn glances over at Vidocq.

"Eugene, I didn't know that you knew the sultan of Brunei."

"What does that mean?" I ask.

"You're not the sultan? Perhaps you're Bill Gates or the czar of all the Russias?"

"No."

"Then trust me. You can't afford Spiritus Dei."

The little man wanders to a nearby table and picks up a wooden doll that looks like it was pulled out of a fire. He winds a key at the doll's back. It stands up and begins to sing. The song might be a hymn or an aria from an opera I've never heard of, which is all of them. The doll's voice bounces off the walls, high, perfect, and heartbreaking. With a soft click, the key in its back stops moving and the doll falls over. Its voice echoes for several minutes, bouncing off the labyrinth's thick walls.

"Of course, we might be able to do a trade," Muninn says. "There's a certain someone who would like a certain something in the possession of certain other people in our little town. I would like you to help Eugene procure this item for me. If you're successful, I guarantee you a flask of Spiritus Dei and a not inconsiderable amount of cash. Eugene told me that you'd like money to be part of your payment. Is that right?"

"Money is good."

"Money I have."

Muninn brings over a set of blueprints he'd hidden behind a collection of canopic jars. He spreads the blueprints on the only relatively uncluttered table in the room, first pushing animal teeth, Mayan vases, and a box of lenses and prisms out of the way.

"The place you are invading is called Avila. It's a gentleman's club in the hills."

"What does that mean, 'gentleman's club'?"

"Just what I said. A gentleman's club. In the old sense. A place to drink, to eat, and to gamble with friends. It's also the most exclusive and expensive bordello in the state. Perhaps the country. Avila's clients are film producers, software billionaires, local politicians, and foreign heads of state. Only the highest of the high can get inside. Except for you two, of course. You'll be the rats in the walls."

The building on the blueprints is round and the interior is laid out in concentric circles.