Lucian turned to Kate. “Do you want to explain?”

“When Chandra . . . when the experts at our CDC had isolated the Jvirus,” she said, “it became easy in retrospect to, notice the effect on wholeblood and immunodeficient precultured samples. The Jvirus . . . it's really a retrovirus . . . binds gp120 glycoprotein to CD4 receptors in Thelper lymphocytes“

“Whoa, whoa,” said O'Rourke. “You mean you can just look at blood samples in a microscope and tell if they're strigoi?”

Kate paused and looked at Lucian. “It's not quite that simple. We can't just look in the eyepiece, but .... yes, you can tell a difference when the Jretrovirus interacts with alien blood cells. “

Lucian set the first slide in place. “Did you discover the amazing ratio of infected cells?” He was talking. to Kate.

“We placed it at almost ninetynine percent,” she said.

“What does that mean?” asked O'Rourke.

Kate explained. “The HIV retrovirus goes after about one CD4 cell in a hundred thousand. That's a lot when you realize how many billions of cells we have. But the Jvirus . . . well, it's greedy. It tries to infect all of the alien blood cells it encounters.”

O'Rourke took a step away from the counter. His face looked very pale above his dark suit and Roman collar. “But it can't be that contagious . . . we'd all be vampires . . . strigoi . . . if it worked like that.”

Kate made herself smile. “No, it's not contagious at all, as far as we can tell. It's generated in the host's body by a complex recessiverecessive gene trait that we don't understand. It's also codependent upon the SCIDtype immune deficiency disease that comes as part of the package.”

“Which means?” said O'Rourke.

Lucian answered without lifting his face from the microscope. “Which means that you have to be dying of a rare blood disease in order ,to gain virtual immortality from the same disease. It's not catching.” He looked up. “Although we might all wish that it were. Who goes first?”

Kate made a “you first” gesture.

“Awesome, dude,” said Lucian in his mock mutant turtle dialect. He lifted a lancet, pricked his finger, squeezed enough blood free so that he could transfer a smear to the prepared slide, and handed the lancet pan to Kate. “You want to do the honors with our Father here?”

Kate swabbed O'Rourke's middle finger, drew blood, prepared his slide, and did the same forherself. “I still say that this proves nothing,” she said.

Lucian spent several minutes treating the samples while Kate watched. “Well, at least it proves that we can't see any little vampire platelets in my sample,” he said at last, standing back from the microscope. Kate bent over and peered through.

O'Rourke waved away his turn. “I could never see anything but my own eyelashes,” he said. “What's all the stuff you're doing to it?”

Kate's sample went onto the slide tray next. “Preparing it for an assay to check reverse transcriptase,” said Kate.

O'Rourke sounded disappointed. “So we couldn't see little vampire platelets even if we tried?”

“Sorry, dude,” said Lucian and brought out a centrifuge that Kate thought looked as if it had been designed in the Middle Ages. “But the assay shouldn't take too long.” He held up a clean vial. “Now I want to take one more sample.”

Kate had the impulse to glance over her shoulder. She wondered what she would do if someone were standing in the shadows there. “From whom?” she said.

“Exactly,” said Lucian. He doused the light and led them by penlight down the corridor, back into the basement, and then down another flight of stairs into an even deeper basement.

Kate smelled it first. “The morgue,” she whispered to O'Rourke.

Lucian stopped at the last set of swinging doors. “It's OK. This is the old morgue. The students and teachers use the newer, smaller one in the west wing. But this is where the cadavers are stored before the students get them. And sometimes the city uses it as an overflow depot for unclaimed bodies. “

“Mr. Stancu from the Ministry?” said Kate.

“Yeah, this is where I saw him. But my letter to you wasn't totally candid, Kate. I'd been tipped by a friend in the Order that Stancu had been murdered. Just like Popescu.”

“Can we meet this friend of yours?” said O'Rourke.

“No.”

“Why not?”

“He was murdered the same week they killed my parents,” said Lucian. “They cut his head off. “ He opened the doors and the three of them went into the chilly darkness. Bare steel tables with ceramic basins and pedestals loomed in the darkness. They were not clean.

“You know,” said O'Rourke, his voice flat, “that we only have your word that your parents were killed.”

“Mmhmm,” agreed Lucian. He handed the penlight to Kate. “Thank you,” he said as she held it steady. He opened a door and slid the long tray out. Lucian lifted the sheet.

“Kate, do you recognize?” said Lucian, his voice very tight.

“Yes.” The last time she had seen Lucian's father, the man had been complimenting her in French, laughing, and pouring more wine for everyone at the table. Now it looked as if his throat had been cut in two places. His skin was very white.

Lucian closed the drawer and opened the one next to it. “And this?”

Kate looked at the middleaged woman who had blushed with pleasure at Kate's invitation for the Forsea family to visit her in Colorado when Lucian brought them over after finishing medical school. Mrs. Forsea had done her hair especially for their afternoon meeting. Kate could still see a curl of the graying hair. The throat wounds were almost identical to her husband's.

“Yes,” said Kate, grasping O'Rourke's hand and squeezing without meaning to. What if they were actors? Not really Lucian's parents? The whole thing a complex plot? Kate knew better.

Lucian slid the drawer shut.

“Is this what you wanted to show us?” said O'Rourke.

“No.” He fumbled with the ring of keys and unlocked a heavy steel door set in the far wall. It was colder and darker in the next room, but Kate could see glowing dials and diodes illuminating a low, metal cylinder that looked like one of the steel watering tanks she had seen on ranches in Colorado. The surface of the tank was bubbling and broiling.

Two steps closer and Kate stopped, her hands flying to her face.

“Jesus!” breathed O'Rourke. He raised one hand as if to cross himself.

“Come,” whispered Lucian. “We'll take the final sample. “ He led them forward.

The steel tank was about three feet deep and seven feet long and it was filled with blood. At first Kate could not believe it was blood despite the color revealed in the dim light and the obvious viscosity, but Lucian had watched her reaction and said, “Yes, it is whole blood. I stole it from District One Hospital and other places. Much of it comes from the American relief agencies.”

Kate thought of the dying children who had needed whole blood transfusions while she was working in Bucharest the previous May, but before she could snap something at Lucian she saw what floated in the tank just beneath the rolling surface.

“Oh, my God.” She had whispered. Now, despite her horror, she leaned closer to peer into the tank, squinting in the red and green glow from the dozen or so medical instruments that clustered at one end of the trough, insulated leads and cables flowing into the bath of slowly ,bubbling human blood.

It was . . . or had been . . . a man, naked now, eyes and mouth wide open as the face floated just beneath the surface. Different parts of his body gleamed in the oily light as unseen currents in the blood moved him to the surface and then let him submerge again. He had been slashed almost to pieces with what lookedto Kate's eye, trained to trauma woundsto have been a large, bladed weapon.

“A sharpened shovel,” said Lucian, as if reading her mind. Kate licked her lips. “Who did it?” She knew what Lucian would answer.