'Typically, once you're in here, they don't let you out.' She shut the drawer.

'This isn't typical.' I tied down the hood and turned on my air. 'The case this morning is mine.'

I could tell she was one of those nurses who resented women doctors, because she preferred to be told what to do by men. Or maybe she had wanted to be a doctor and was told that girls grow up to be nurses and marry doctors. I could only guess. But I remembered when I was in medical school at Johns Hopkins, and one day the head nurse grabbed my arm in the hospital. I'd never forget her hate when she snarled that her son hadn't gotten in because I had taken his slot.

Fujitsubo was walking back into the room, smiling at me as he handed me a telephone and plugged it into a jack.

'You got time for one.' He held up his index finger. 'Then we got to roll.' I called Marino.

Bio Level 4 containment was in back of a normal lab, but the difference between the two areas was serious. BL-4 meant scientists doing open war with Ebola, Hantavirus and unknown diseases for which there was no cure. Air was single-pass and negative pressure to prevent highly infectious microorganisms from flowing into any other part of the building. It was checked by HEPA filters before it entered our bodies or the atmosphere, and everything was scalded by steam in autoclaves.

Though autopsies were infrequent, when they were performed it was in an air-locked space nicknamed 'the Sub,' behind two massive stainless steel doors with submarine seals. To enter, we had to go in another way, through a maze of change rooms and

showers, with only colored lights to indicate which gender was in what. Men were green so I put my light on red and took everything off. I put on fresh sneakers and scrubs.

Steel doors automatically opened and closed as I passed through another air-lock, into the inner change, or hot side room where the heavy gauge blue vinyl suits with built- in feet and pointed hoods hung from hooks on a wall. Sitting on a bench, I pulled one on, zipping it up and securing flaps with what looked like a diagonal Tupperware seal. I worked my feet into rubber boots, then layers of heavy gloves, with outer ones taped to cuffs. I was already beginning to feel hot, doors shutting behind me as other ones of even thicker steel sucked open to let me into the most claustrophobic autopsy room I had ever seen.

I grabbed a yellow line and plugged it into the quick-release coupling at my hip, and rushing air reminded me of a deflating wading pool. Fujitsubo and another doctor were labeling tubes and hosing off the body. In her nakedness, her disease was even more appalling. For the most part, we worked in silence for we had not bothered with communication equipment, and the only way to speak was to crimp our air lines long enough to hear what someone else was saying.

We did this as we cut and weighed, and I recorded the pertinent information on a protocol. She suffered the typical degenerative changes of fatty streaks and fatty plaques of the aorta. Her heart was dilated, her congested lungs consistent with early pneumonia. She had ulcers in her mouth and lesions in her gastrointestinal tract. But it was her brain that told the most tragic story of her death. She had cortical atrophy, widening of the cerebral sulci and loss of the parenchyma, the telltale hints of Alzheimer's.

I could only imagine her confusion when she had gotten sick. She may not have remembered where she was or even who she was, and in her dementia may have believed some nightmarish creature was coming through her mirrors. Lymph nodes were swollen, spleen and liver cloudy and swollen with focal necrosis, all consistent with smallpox.

She looked like a natural death, the cause of which we could not prove yet, and two hours later, we were done. I left the same way I had come in, starting with the hot side room, where I took a five-minute chemical shower in my suit, standing on a rubber

mat and scrubbing every inch with a stiff brush as steel nozzles pounded me. Dripping, I reentered the outer room, where I hung the suit to dry, showered again and washed my hair. I put on a sterile orange suit and returned to the Slammer.

The nurse was in my room when I walked in.

'Janet is here writing you a note,' she said.

'Janet?' I was stunned. 'Is Lucy with her?'

'She'll slide it through the pass box. All I know is there's a young woman named Janet. She's alone.'

'Where is she? I must see her.'

'You know that isn't possible just now.' She was taking my blood pressure again.

'Even prisons have a place for visitors,' I almost snapped. 'Isn't there some area where I can talk to her through glass? Or can't she put on a suit and come in here like you do?'

Of course, all this required permission, yet again, from the colonel, who decided that the easiest solution was for me to wear a HEPA filter mask and go into the visitors' booth. This was inside the Clinical Research Ward, where studies were conducted on new vaccines. She led me through a BL-3 recreation room, where volunteers were playing Ping-Pong and pool, or reading magazines and watching TV.

The nurse opened the wooden door to Booth B, where Janet was seated on the other side of glass in an uncontaminated part of the building. We picked up our phones at the same time.

'I can't believe this,' was the first thing she said. 'Are you all right?'

The nurse was still standing behind me in my telephone-booth-sized space, and I

turned around and asked her to leave. She didn't budge.

'Excuse me,' I said, and I'd about had it with her. 'This is a private conversation.' Anger flashed in her eyes as she left and shut the door.

'I don't know how I am,' I said into the phone. 'But I don't feel too bad.'

'How long does it take?' Fear shone in her eyes.

'On average, ten days, at the most fourteen.'

'Well, that's good, then, isn't it?'

'I don't know.' I felt depressed. 'It depends on what we're dealing with. But if I'm still okay in a few days, I expect they will let me leave.'

Janet looked very grown-up and pretty in a dark blue suit, her pistol inconspicuous beneath her jacket. I knew she would not have come alone unless something was very wrong.

'Where's Lucy?' I asked.

'Well, actually, both of us are up here in Maryland, outside Baltimore, with Squad

Nineteen.'

'Is she all right?'

'Yes,' Janet said. 'We're working on your files, trying to trace them through AOL and UNIX.'

'And?'

She hesitated. 'I think the quickest way to catch him is going to be online.' I frowned, perplexed by this. 'I'm not sure I understand…'

'Is that thing uncomfortable?' She stared at my mask.

'Yes.'

I was sorrier for the way it looked. It covered half of my face like a hideous muzzle and kept knocking the phone as I talked.

'How can you catch him online unless he's still sending messages to me?' She opened a file folder on her Formica ledge. 'Do you want to hear them?' I nodded as my stomach tightened.

'Microscopic worms, multiplying ferments and miasma,' she read.

'Excuse me?' I said.

'That's it. E-mail sent this morning. The next one came this afternoon. They are alive, but no one else will be. And then about an hour after that, Humans who seize from others and exploit are macro parasites. They kill their hosts. All in lowercase with no punctuation except spaces.' She looked through the glass at me.

'Classical medical philosophy,' I said. 'Going back to Hippocrates and other Western practitioners, their theories of what causes disease. The atmosphere. Reproducing poisonous particles generated by the decomposition of organic matter. Microscopic worms, et cetera. And then the historian McNeill wrote about the interaction of micro and macro parasites as a way of understanding the evolution of society.'