On the far side of the room, a set of stairs led up to a raised metal platform. The mezzanine floor was filled by a bank of computers, all humming busily, and sitting at the hub computer was Rebecca Simmons. Her hair was still blue, which was probably a record, since she normally changed its color every few days. She waved as we walked in. I could see that she was in the middle of eating something, although from this distance I couldn't quite tell what it was.

"Hey, Becka," I called. "Any luck on manipulating that photo of Sebastian and Sabine yet? I'm still gambling that we might be able to see a reflection from those pretty blue eyes of hers."

Rebecca managed to look chagrined. "I'm still working on it. We've managed to peel away the two images, but it'll still take some work to enhance the reflection. I'll definitely let you know as soon as I find something, though."

"Thanks. At this point, any clue will help."

"Which is why we're here," Selena said, climbing the stairs. "Have you got the simulation program booted up?"

"Just finished debugging it five minutes ago." Rebecca smiled. "I put in the new data that you asked for, and it's ready to go whenever you are."

As I followed Selena up the stairs, I saw what Rebecca had been eating-there was a plastic bag full of sunflower seeds on the metal desk next to the hub computer. I noticed a few discarded seeds littering the floor.

Selena looked at the bag, and her eyes narrowed. "Aren't you the one who's always getting mad at us for touching the equipment, Becka? Why don't you just get a salad bar installed in here?"

She blushed. "Sorry-I'm bloody starving. Marcus had me doing network maintenance for most of the morning, and then two hub computers in the serology lab went down. I've just spent the last thirty minutes debugging this sim program, and after that, I have to figure out why Ben keeps getting Viagra spam e-mail on his laptop." She rolled her eyes. "I've barely eaten all day."

Selena sighed. "Just try not to get any crumbs on the fiber-optic plates. I don't know how we'd explain that to Marcus."

"Next time, I'll bring a bib." She smiled. "So are you ready?"

"Sure." Selena gestured for me to follow her, and we climbed down the stairs again, positioning ourselves in the center of the chamber. "Fire it up."

"All right. I'm activating the image matrix now." She pressed several buttons, and a low hum began to emanate from the wall panels. "Hope nobody's using the microwave, because this baby takes a lot of power."

"It'll be a tragedy if Ben's burrito comes out only half-defrosted, " I said.

"I wish Ben could be half-defrosted," Selena replied. "Would do him good."

Rebecca hit the lights, and for a moment, the room was almost completely dark-save for the glow of the computer screens. Then a soft, pale blue light began to emanate from the fiber-optic panels. The light grew more intense, until it culminated in a bright flash that left me rubbing spots from my eyes.

When I could see again, I was standing in Cassandra's living room.

The Nerve was incredible. It had replicated Cassandra's house exactly, down to the exact shade of her chocolate brown carpet and black couch. There was a coffee table next to the couch, and standing on either side of it were two figures. I recognized them as Sebastian and Cassandra.

I resisted the urge to walk up to Sebastian and peer into his eyes. I knew that the 3-D digitization was perfect, down to the very last pore and stray hair. Cassandra, too, was completely lifelike. They both stared straight ahead, standing on either side of the table, saying nothing. Audio wasn't a part of the simulation. Most of the time, it wasn't needed anyway.

"All right," Selena said. "We're assuming that, at some point in the evening-shortly before he died-Sebastian paid Cassandra Polanski a visit at her house. We can only imagine what they talked about."

"Mia." I swallowed. "Sebastian must have known something. Maybe he knew that Mia was already infected with the vampiric retrovirus. Hell, maybe he was the one who turned her. Either way, Cassandra didn't like what he had to tell her."

"Continue with the simulation, Becka," Selena said.

Before my eyes, Cassandra took a step forward and gestured with her right hand in Sebastian's direction. Sebastian crumpled soundlessly to the floor-dead.

Cassandra reached down and picked up Sebastian's body. She struggled briefly with the weight, then swung him over her left shoulder.

"Wait," Selena said. "That's not right."

"That's the data you gave me," Rebecca protested.

"Yeah, but I forgot about something. We found a partial print on the bottom portion of Sebastian's thigh. It was the only mark that we could find on his body, and that was only after we fumed it. The print was too smudged for us to match with anything, but now that we know more, I'd bet that it was Cassandra's. For that print to have gotten on his thigh-"

"She carried him differently," Rebecca interjected. "I see where you're going. Just let me make a minor change to the program. It might flicker a bit, since I don't have time to properly debug it."

The image of Cassandra and Sebastian shimmered for a moment, and then they were standing in their original positions again. I saw Cassandra gesture once more, saw Sebastian fall for the second time. But then, as Cassandra picked his body up, she held him close to her chest this time-with one arm wrapped around his legs.

"She cradled him," I said quietly. "Like a parent carrying a small child. She didn't want to hurt him. She must have felt incredibly guilty."

"She still murdered him," Selena said.

"Yes, but we don't know what they talked about. Maybe Sebastian threatened her. Maybe he threatened Mia's life-"

"A weak little bird like him? You said that he was a submissive. He was basically that Sabine woman's trained bitch. No way he would have blazed in there and started threatening a powerful demon like Cassandra. It doesn't make sense."

"We might never know."

"I'm loading the second part of the program now," Rebecca said.

There was another flash of light, and when it cleared, we were standing back in the alley on Granville Street . We watched Cassandra carry Sebastian's body into the alley, then carefully lay him down on the ground.

"She posed him," Selena said. "She wanted us to find him that way-wanted us to investigate."

Cassandra laid out Sebastian's body, folding his arms across his chest, as if he were merely sleeping. Wearing gloves, she removed his wallet and slipped it inside her own jacket.

"Of course, we're just extrapolating here," Selena continued. "We don't know what Sebastian was originally carrying, or what Cassandra took from him. If he had a wallet, we never found it. But she must have put on gloves after the fact, since we found that one partial print on his thigh."

"What about the note? And the photo?"

Selena shrugged. "Maybe she planted them both. Maybe she saw them and decided to leave them there. Or maybe she was flustered and missed them. Either way, she wanted us to find the kid's body. She was leading us to something."

"You think she wanted to be caught?"

"No. I think she wanted us to catch someone else. But the plan ended up backfiring, because they got to her before we could get to them."

"Running part three of the program now," Rebecca said.

When the third flash of light cleared, we were standing in Cassandra's office. There were four figures before us. Cassandra was standing in front of the desk. The first Vailoid demon was positioned directly in front of her, and the second one was standing by the window. There was also a fourth figure, who was just a dark outline, standing in the corner of the room.

"That fourth figure is our mystery player," Selena said. "The person who took out the second Vailoid demon. Possibly the person who hired them in the first place to kill both Cassandra and Mia. We still don't know for sure exactly what Cassandra was doing at SemTec Laboratories, but she did test Mia's DNA. Her prints were all over the equipment. So she must have known that the girl was infected. She probably found out shortly before the Vailoid demons arrived."

"I'm running the final part of the program now," Rebecca said.

As I watched, the first Vailoid demon approached Cassandra. She gestured again with her right hand, and the demon began clutching its head. Then, horribly, it reached out and plunged its hand into Cassandra's chest. Normally, the sim-room could re-create precise blood splatter, but Rebecca had been kind enough to remove that function from this particular program. Both Cassandra and the demon fell to the ground at the same time. As the second demon walked over to finish off Cassandra, the first demon began crawling in vain toward the window.

I felt like some kind of deity, watching this silent, terrifying masque play out before me.

Cassandra was lying on the ground, still. The demon that she'd mortally injured was lying next to the window, eyes staring straight ahead.

Then the fourth figure-the figure without a face- advanced upon the second demon. As the demon turned, the figure did the exact same thing that the first Vailoid demon had done to Cassandra. It plunged a hand into the demon's chest. But it was a lot more creative about it.

The figure reached its other hand into the gaping chest cavity, and pulled outward, shearing through the rib cage and literally tearing open the Vailoid's chest completely. Then it threw the demon's ruined body across the desk, where it lay there, bleeding and still.

"Tasha had originally thought that some sort of magical force ripped through the demon's chest," Selena said. "But she took another look at the X-rays, and found claw marks on the rib cage that she'd missed before. Whatever did this to the demon must have used its bare hands."

The fourth figure then grabbed the first demon's body and threw it out the window. Glass shattered in all directions, and the demon abruptly vanished in a spray of pixels. There was no need to map its trajectory through the air. We knew what happened after it hit the ground.

What we didn't know was how the fourth figure escaped. There was no data for that-so the figure just remained there, voiceless and faceless, staring at us.

I shivered.

"We originally thought that whoever killed Sebastian must have also killed the second Vailoid demon," I said, "and that he, or she, then threw the body out the window to cover up the brain trauma and make it look like the fall killed it. But we had the identities switched around. It was Cassandra who killed Sebastian, and then Cassandra again who killed the first demon-using her telekinesis both times. Then this mystery figure killed the second demon, but left its body on the desk for us to find."

"It wanted us to think that Cassandra was a lot more dangerous, " Selena said. "That she was capable of tearing a demon apart with her bare hands. But she was actually desperate, and using her powers to defend herself. Her only premeditated murder was Sebastian, and even that might have been impulsive. If he threatened Mia, or hinted that she might have been infected-maybe Cassandra freaked out and killed him, thinking that she was protecting the kid."

"But she's obviously got a more ominous role in this," I added, "if we consider all of the coincidences surrounding Mia's parents and their disappearance, the custody papers that get conveniently signed only two weeks before Mom and Dad both vanish, the complete lack of material on Cassandra before 1998-I'm starting to think that this was all some kind of deal that went sour."

Selena nodded. "You mean that Cassandra knew the person who killed her-that they were working together."

"In some capacity, yes. I think they must have hatched some sort of deal to get rid of Mia's parents, and Cassandra was the one who would look after Mia until she reached a certain age. Why her birthday was important, and what they planned on doing with her-that, I don't know. But something went wrong, and Cassandra obviously wanted to protect Mia from her partner, or partners. She failed."

We both stared at Cassandra's lifeless body. I flashed back to that night at the office, when I first saw her lying there by the desk, bleeding. The look on Mia's face. The sound of her world crumbling to dust.

"You can shut down the program now, Becka," I said.

Rebecca pushed a few buttons, and the image vanished. We were left in the white-walled sim chamber, listening to the contented hum of the computers.

"This all just brings us back to our first mystery," Selena said. "What sort of killer is brilliant, connected, powerful enough to tear apart a demon with its bare hands, but conscientious enough to mix up the evidence-"

"Aware of the vampire community," I continued, "knowledgeable enough to seek out a rare type of healer-demon, like Cassandra, who normally wouldn't live anywhere near this area-"

"Obsessed with a teenage girl"-Selena shook her head-"and fond of rare yellow silk?"

Rebecca chuckled softly. "You OSIs and your mysteries," she said.

24.

The pillows were on fire. They looked like pink creampuffs, slowly melting as the flames consumed them. Everything in Eve's bedroom was pink-it had been, after all, her favorite color. I'd always liked gray myself. Even as a little kid, I always wanted to wear gray hooded sweatshirts and formless gray slacks, like I had already become an old maid. Lucy Snowe from Bronte's Villette, fighting with my outraged sense of adolescent Protestantism while swaying to the Catholic sexiness of French professors. But Eve liked pink. She had a pink ruffled bedspread, pink pillows, and pink shoes-now seething with smoke against what used to be her soft beige carpet. Pink gumballs were cooking in her very own gumball dispenser, which had become a wreck of molten plastic and cheap metal. I remembered the taste of them-almost too sweet, like you could barely stand it.

I dragged myself along the carpet. I could feel the edges of my heat shield beginning to waver, and the power was dragging on me, threatening to slack off like an abandoned rope. At thirteen, all of my magic was an exercise in torsion, my will against the universe, but there's only so long that you can keep that kind of intensity up. I hadn't learned about focus yet. All I knew was how to channel my will, and right now, every ounce of it was pouring into the shield. In a few moments, I'd be bone-dry, and then the flames would rush in.

I almost wanted to let them.

"Eve!"

I pushed aside a broken lamp and crawled behind the bed. The window was blackened-I couldn't see the outside world anymore. There was only this-the hell of flames, the flush of killing heat on my skin. Maybe the earth was gone. Maybe I really was in hell, and my eternal punishment would be to remain in this room, always, looking for a hidden girl. Looking for a- It was some kind of gas leak, I think. They weren't clear.

-her blackened body- Maybe someone left one of the elements on. Such a tragedy. Nobody else was there-the poor thing was all alone. She was a latchkey kid, after all.

-frozen in a boxer's pose, hands clenched to her chest- -muscle and bone fused, tendons boiled until they were soft, pliable- A girl her age should have been out playing with friends. What would she be doing home in the middle of the day? So odd.

-and a filigree of light around her, a pattern, maybe smoke- The firemen came too late. She was already- -was it her soul? That tracery of silver, that snowflake? Was it?

You can't see her. You don't want to see her.

Honey, she's already- But it wasn't my mother standing in the hospital. It was Lucian. He was surrounded by black flames, what Milton called "darkness visible," fire licking at his skin without leaving a mark.

"Tess, she's already gone." His eyes were two black "lunettes," sucking all the light from the room. They were worse than the fire, worse than all the dying. That unsigned space, that nonlife, the grave where a soul turned endlessly, polished and hewn to icy marble. We both surveyed each other across the frozen bier of the dead or dying universe, like unfamiliar lovers on a hotel bed.

"You're gone." He raised his hand, and a black moth unfolded itself in his palm, fluttering, ecstatic against his flesh. I could see the powder on its wings.

There are over 60,000 distinct species of blowfly in the world. How can a person not love entomology? Each fly is like a small black equation in the air, lighting upon a blade of grass or a dead body without discrimination. Even if you die in secret, in silence, in the darkest of sealed chambers, a blowfly will find you in minutes. So you're never alone. Not really.

The CORE's special entomology lab-which dealt with both terrestrial insect varieties and mystical hybrids of the sort that you didn't really want to meet-was overflowing with genus charts and diagrams of succession. Bugs on pushpins and cards, hundreds of individual families with all of their blood feuds and hereditary disputes: Calliphorae, Diptera, horned beetle, blood scarab. Leigh Mussell, the director, had one butterfly on her desk with its wing covers gently scraped away, so that you could see the delicate veins underneath, like a hidden city. Even maggots have veins, teeth, a circulatory system, taking in shallow pockets of air through tiny spiracles in their flesh. Under the SEM, they look like gorgeous silken islands, or neural sulci. I was at a scene once where they had climbed up the trees in search of a safe place to pupate. It was literally raining maggots. Poor Derrick had to run back to the car to get us umbrellas.

People follow laws of succession as well. They arrive at scenes sometimes, when they're told, do their business, and leave. They abandon a dark shape, the empty room where love used to shelter, a hollowed-out comma of delicate space.

Lucian stroked the wings of the moth with his fingertips, so careful that he didn't brush away any of the precious dust-actually tiny scales that felt like the most delicate of talcum powders against your skin. He extended his other hand. If I'd been able to put that gesture, frozen in time, underneath a scanning electron microscope, I would have seen thousands of electrons splitting their shells, protons changing their spin and flavor, blazing into new atomic valences.

"Who are you?" I grabbed at his wrist, but the black flames swept over me. They felt like a thousand wings dusting my mouth and eyes, the voices of the dead. And whatever came after.

I stared at the hairs on his wrists. What would it be like to fuse my hands to his, epiphysis, bone spur, metacarpal, surrendering like wax? I thought of the carelessness with which men washed their hands. The warm water passing over his palms as he washed them, unthinking, hand over hand in automatic motions. To be inside those hands, in the column of warm water.

To be the fine hairs on those wrists, the dermal papillae just beneath the skin, erytheic, blushing.

I pulled away. "You necromancers are so fucked up, you think you can control life and death like a game of poker- but the universe doesn't work that way! There are always consequences-you can't play with those kinds of forces. Everything you do leads you closer to-"

He stared at me. "To what, Tess?"

His eyes were loud. I could hear them; the shadows they made, the flutter of their gaze, like the many-tongued angels that guarded the ark, a skein of wings and open fingers and grazing mouths.

I realized then that I didn't know. I didn't know anything. It was a two-way mirror-I couldn't see into the void, but it was watching me. It could see everything. Just biding its time. And I didn't know if light and redemption and-hell, even forgiveness-waited for me on the other side, or something else entirely.

"Everything has consequences," he said. "Especially this."

"But what is this?" I glared at him. "What are we doing here?"

He was silent.

Suddenly, all I could feel was anger. Lucian and his shadowy competence, his ease, walking into my dreams like some careless sheik and handing me fucking riddles. I imagined him as a cocky teenager. Guys like him, laughing and prancing on the soccer field in their shorts, which flared against the warm air like bits of brightly colored foil or winking eyes. I liked legs. I was fascinated by the curve of a man's leg, how it could be muscular and covered in a soft sheen of dark hair-I knew how it could feel, like spider silk, or the satiny edge of that old baby blanket that you used to drag around the house. Mom says I constantly referred to my blanket as "the stem," since it was really just a frayed piece of sky blue silk that curled around my arm, and I couldn't pronounce "satin." Never good with words and their consequences.

I think myelin must feel that way-the silvery connective substance blanketing our nerves that allows them to communicate through synaptic conduction. Our thoughts, our moods, everything that comes out of us is regulated and made possible by that shimmery floss, diaphanous, subtle as a bee's wings on your tongue or the silken remnant left behind by a beetle pupating, what Leigh would have called "frass."