Briskly, but not as if she had to hurry, Kate flashed her passport and boarding pass. The young guard waved her by.

At the bottom of the stairs there was another counter, another security guard. Kate could see the last of the passengers boarding the transfer, jitney outside. The tractor engine started in a rush of smoke. Kate focused on the outside door and started to walk past the guard.

“Stop!”

She stopped, turned slowly, and forced a smile on her face. Joshua squirmed but did not cry.

The guard had a fat face and small eyes. His pudgy fingers tapped the counter. “Passport.”

Kate set it down without comment and tried not to fidget while the fat man looked it over carefully. There were footsteps and voices just out of sight up the stairs.

Outside, the last of the passengers and baggage had been loaded on the two trailers. The tractors roared their engines. “We'll be late,” Kate said quietly to the guard.

He lifted his pig eyes and scowled at her and the baby.

She held his gaze in silence for the better part of a minute. The baggage jitney pulled away. The passenger jitney waited to follow it the hundred yards out to the aircraft.

When she had been a practicing surgeon, Kate had often commanded colleagues or nurses to hurry with nothing more than the strength of her gaze above the surgical mask. She did so now, putting every once of authority she had earned in her life and career into the look she gave the guard.

The fat man looked down, stamped the passport a final time, and brusquely handed it to her. Kate forced herself not to run with Joshua in her arms. The jitney had already begun rolling toward the aircraft, but it stopped and waited while she caught up and stepped aboard. The Polish and Romanian passengers stared at her.

They were on the aircraft twelve minutes before it taxied to the head of the runway, but Kate was sure that her watch had stopped. It seemed like hours, days. She watched out the streaked window as two security men in leather jackets joked and smoked at the foot of the stairs. They were not the two men from the terminal. But they carried handheld radios. Kate closed her eyes and came as close to praying as she had since she was ten.

Three airport workers rolled away the stairs. The plane taxied to the end of the deserted runway. No aircraft had taken off or landed since they had boarded. The plane accelerated down the patched runway.

Kate did not breathe deeply until the landing gear was up and Bucharest was a scatter of white buildings rising above chestnut trees behind them. Her hands continued to tremble until she knew they must be out of Romanian airspace. Even at the Warsaw airport she felt her heart pounding until they changed crews and lifted off for Frankfurt.

Finally the pilot's voice came over the intercom. He had an American accent. “Ladies and Gentlemen, we've just leveled off at our cruising altitude of twenty-three thousand feet. We've just passed over the city of Lodz and should be coming up on the German border in . . . oh . . . five minutes or so. We've had a bit of rough weather, as I'm sure you noticed, but we've just passed the tail end 'of that front and Frankfurt informs us that it's sunny and very warm there, temperature thirty-one degrees Centigrade, winds out of the west at eight miles per hour. We hope you enjoy the rest of the flight.”

Sunlight had suddenly streamed through the small window. Kate kissed Joshua and allowed herself to cry.

Kate Neuman blinked away the glare from the sunlight that had made its way through Boulder CDC's tinted windows and answered the phone. She honestly could not have said how long it had been buzzing. She vaguely remembered her secretary sticking her head in the office to announce she was running down to the cafeteria for lunch.

“Doctor Neuman,” said Kate.

“Kate, this is Alan down in Imaging. I have the newest pictures from your son's last workup.”

“Yes?” Kate realized that she had been doodling circles within circles until her memo pad was almost black. She set the pen down. “How do they look, Alan?”

There was the briefest hesitation and Kate could imagine the redheaded technician sitting in the glare of his multiple display monitors, a halfeaten corned beef sandwich on the terminal in front of him.

“I think you'd better come down, Kate. You should see this yourself.”

There were six video monitors set into the long console and each of them displayed a slightly different view of nine-monthold Joshua Neuman's internal organs'. These were not X rays but complex images built up by Alan's magnetic resonance imaging equipment. Kate was able to make out her child's spleen, liver, the sinuous curves of the upper small intestine, the lower curve of his stomach ....

“What is that?” she asked and stabbed a finger at the center monitor.

“Exactly,” said Alan, pushing his thick glasses up and taking a bite of his corned beef sandwich. “Now, watch when we run the sequence with the CT data from three weeks ago. “

Kate watched the primary VDT as the images coalesced, rotated in three dimensions, zoomed in for a closer look on the lower curve of the stomach, differentiated layers of stomach lining with false colors, and then ran a timelapse sequence with digital enhancement.

A small appendix or abscess seemed to grow in the wall of Joshua's stomach.

“Ulcer?” said Kate, knowing that it was not one even as she said the word. The magnetic resonance imaging showed solid structure in the anomaly. She felt her heart sink.

“No,” said Alan, taking a sip of cold coffee. Suddenly he saw Kate's face and he jumped to his feet and slid a chair under her. “Sit down,” he said. “It's not a tumor either.”

“It's not?” Kate felt the vertigo lessen. “But it has to be.” “It's not,” said Alan. “Trust me. Watch. This is the CTenhanced series from this week's MR imaging.”

The lower curve of stomach was normal again. Colored layers proliferated, the abscess or whatever it was appeared, grew as substantial as an appendix, and then began to shrink.

“A separate growth?” said Kate.

“Same phenomenon, different time period.” Alan pointed to the data column to the right of the image. “Notice the correspondence?”

For a moment Kate did not. Then she leaned closer and rubbed her upper lip. “The same day that Josh received the plasma. . . “ She wheeled her chair over to the monitor where the previous cycle had been frozen on the screen. Running her finger down the screen, she said, “And the same date three weeks ago that he had a transfusion. These images show some change in the baby's gut whenever he receives blood?”

Alan took a healthy bite of sandwich and nodded. “Not just a change, Kate, but some sort of basic adaptive process. That structure is there at other times, it just becomes more visible when it's absorbing blood . . .”

“Absorbing blood!” Kate's shout surprised even herself. She modulated her voice. “He's not absorbing blood through the stomach wall, Alan. We give Joshua intravenous injections . . . we don't give him a baby bottle with blood in it!”

Alan missed the irony. He nodded and finished chewing. “Of course, but the adaptation . . . organ . . . whatever it is does absorb blood, there's no doubt about it. Look here.” He touched buttons and all six of the monitors blinked red near the abnormal swelling. “The gut wall there is rich with veins and arteries. It's one of the reasons an ulcer is such a problem there. But this”he touched the image of the tumor like structure“ this thing is fed by a larger arterial network than I've ever seen. And it is absorbing blood, there's no doubt about that.”

Kate pushed her chair back. “My God,” she whispered.

Alan was not listening. He shoved his glasses higher on his nose. “But look at the other data, Kate. It's not the absorption of blood that's interesting. Look at the most recent MR series. What happens next is unbelievable.”