A CT scan was pinned up to a lightbox. The blood clot was a pulpy opacity over and interlacing the second and third lumbar vertebrae. The spine itself had an unusual translucency that I put down to artefact. I wasn't thinking clearly.

Jenkins was standing just beyond the doorframe. Gershon led me to the cramped basin and began washing his hands. The sister next to us had finished her scrub and was now gowning up.

"Want to tell me what's going on?" I asked.

Gershon kept washing his hands.

"You've seen the guy's back. He's had previous spinal surgery, but I don't see any sign of fusion on the scan."

Gershon looked up at me. "It's still not too late for you, Jon. Just wash your hands and let's do this and get you home. Wouldn't you like to go home?"

I nodded dumbly.

"Don't look at the machine. Don't ask any questions."

Home sounded sweet but nothing about this night was part of the bargain. I placed my hands under the stream of water. I moved in the sluggish wash of a trance. Gershon nudged me toward the waiting nurse who handed me my gown.

After the patient was prepped and draped, reduced to a portion of exposed anatomy for us to work on, I made a linear incision across the previous scar. The wound practically slipped open. It was recent work. I couldn't see any trace of suture material. I wondered how this wound had been closed. I was looking at the para-spinal muscles. They should have been scarred-knotted and fibrous and bound together by thick non-absorbable sutures-but they were pristine.

Gershon's theatre cap was soaked with perspiration. Jenkins was watching us as close as ever.

The para-spinals slid easily away from the lumbar pedicles and so far there were no large clots or bone fragments, no telltale signs of any injury. Blood, bone and meat reminded me how much I despised the gross carpentry of spinal work. We spent a few more moments ligating some small bleeders that were quietly seeping into the wound. When I next glanced up, Jenkins was gone, the doorway empty. He was probably having a cigarette or starting World War Three.

"I've done a bad thing," Gershon said quietly. He put a hand over mine in the wound, pressing a large sponge over the vertebrae I'd been trying to expose.

"Your opening could have been neater."

"I've done a real bad thing." He tightened his grip on me.

"How bad?"

"Sometimes in this place..." Gershon's frown creased his mask. "I wasn't thinking it through. I'll take it from here," he offered weakly. "Go. Unscrub."

"You'd be lost."

I shifted his hand and saw what he'd been trying to conceal. I looked back at him, incredulous.

"Having problems, Doctor Wells?" Suddenly Jenkins was standing by my side. He peered into the wound. "Interesting. Much more advanced than we anticipated." The look he gave me now was sly, conspiratorial.

The exposed vertebrae were translucent. I could see the layers of muscle beneath them clearly. My first thought, as I tried to rationalize my vision, was that the bone had been treated with something. But nothing made bone see-through. My mind fought for clarity.

This was some form of prosthesis. It had been fashioned around the entire spinal cord, as if somehow grown. No wonder the scan appeared so strange. Fine wiring laced between the artificial bones. There were no signs of tissue reaction.

No one, anywhere, had a product like this.

I leaned closer. Each vertebra was imprinted with a number. A thick wad of blood sat between the middle vertebrae and the spinal cord. I looked at the cord itself. A string of numbers and letters ran its length. The spinal cord was prosthetic. An outright impossibility.

"What do you make of it, Doctor Wells?"

I was light-headed. Dazed. I glanced out the doorway at the machine and returned my gaze to its pilot's wound. "There's been some secondary hemorrhage," I said. "The initial surgery might be about two weeks old."

I asked for a sucker and removed the clot. An arteriole was pumping away steadily, forming a new pool of blood where the clot had been. I asked for a diathermy wand and coagulated the vessel. Gershon dabbed the wound. There was no fresh bleeding. He wouldn't meet my eyes.

"Nice work, Doctor Wells." Jenkins was still by my side. "You will need to be debriefed, of course."

"I'm fine," I replied. "I'm okay. I just need to go. I need to go home now."

"Of course, Doctor. Everything has been organized for your departure."

Gershon was pale. He looked at me now and the meaning was clear. I'd seen something I wasn't supposed to see and my ongoing silence had to be ensured. I wasn't going anywhere.

I had to do something.

"Knife."

The nurse handed me the scalpel with a curious look. I moved fast.

Jenkins said, "What do you think you're doing?"

"You've seen me use one of these." I had the blade up against his throat. Ran it shakily along the side of his neck, opening the skin. "With my next cut you bleed out. I get it wrong and you drown in your own blood."

The nurse stepped back from the table, knocking a tray of instruments to the floor. The anesthetist and the other nurse had their backs up against a wall, as far away from me as possible.

"Doctor Wells," Jenkins rasped, "such melodrama."

"Jonathan?" Gershon was staring at me, dumbfounded.

"Doctor Wells, what happens after you kill me?"

"That won't be your problem." The four guards were framing the doorway; they leveled their weapons in my direction. "I mean it, they shoot and I take you with me."

"I believe you," he said. "Guards."

Keeping the blade close to the skin I looked in their direction.

"If he does anything to me, shoot Gershon-kneecaps, balls, then abdomen. Then do the same for our guest."

"Greg?" Gershon said.

The guards swung their weapons toward Gershon, who edged back toward the ventilator.

Jenkins said, "Your move."

"Greg, please," Gershon was saying. He collided with one of the oxygen cylinders, then put his hand on it to support himself.

"Clock's ticking, Doctor. I thought you were a gambling man."

I was about to drop the knife when Gershon spoke.

"Greg." His voice sounded different. There was the hiss of escaping gas coming from one of the oxygen cylinders. "Anyone shoots, and we all die," he said.

The guards looked at each other and lowered their weapons.

"You heard the man, Jonathan," Gershon said. "Your move."

He nodded toward the doorway. I shoved Jenkins over to the exit.

"Get out of the way," Jenkins snarled at the guards. The veneer of his composure slipped away.

Gershon elbowed his way past the guards to join me in the main chamber.

"Director," someone said. It was the fucking anesthetist.

I twisted around and shoved Jenkins away from me, back into the room. I should have cut him while I had the chance.

"Director, they're bluffing."

I threw the scalpel wildly in Jenkins' direction. The blunt end caught him in the eye. He reeled backwards, both hands clasped to his face.

Gershon sprinted toward the machine.

I didn't know where else to go.

"Shoot them," I heard Jenkins cry. "Shoot the fuckers."

Two more men stepped out from behind the machine. Flashes leapt from their guns. The room filled with thunder.

"Not the carapace," Jenkins yelled from behind me. "Don't fire at the carapace."

There was the sudden screech of an alarm. Clouds of pale green gas wafted from unseen vents. I'd somehow fallen near one of the machine's supports. Gershon, hunched over, was by my side. The firing stopped. The air was burning in my lungs.

Jenkins' voice crackled from inside a mask. "Let the gas do its work." He was crouched by the entrance to the operating room. Behind him, the anesthetist and nurses were writhing on the floor. I felt an arm grab me as gray film seeped over my vision. I felt myself being dragged. It was cold. Intensely cold. I was being lifted, hauled into the belly of the machine. And that's the last thing I recall.

I woke in the desert.

I was lying on my back, in shadow. It hurt to raise my head, but looking past my feet I could see the furrow my body had made in the sand. The trail was laced with streaks of drying blood. I patted myself down; it wasn't mine.

Above me towered a huge rock formation, tinged red in the last of the sun's rays. It looked familiar. My head throbbed with a dull, heavy ache.

Gershon was sitting next to me, propped up against an abutting shelf of the rock. He said, "You owe me one." His eyes had a partially glazed look.

I asked him where he was hit. He spread his fingers slightly. His gown had an ugly tear across the mid-section. Near its hem were speckles of blood and bone from the operation, but above was a slowly spreading stain.

"I think they nicked one of my renals," he said. "I'll be pissing blood for a month." He smiled wanly. Unconvincingly. He wasn't going to survive the night outside of a hospital.

"Where are we?" I asked.

"The Waste Land," he said, looking around.

The desert was ochre-red in the last of the light. Long shadows stretched across its undulating expanse. I could now make out the enclosing perimeter of low mountains to all sides. I scanned out toward the horizon, past the long, flat surface of the lakebed. No buildings, no hangars, no runway.

"Where's the base?"

"It'll be here in, say, another forty years."

"I really have to get you to a hospital."

Gershon laughed. The laugh turned into a cough that racked his body. The spittle on his lips was flecked with blood. "No hospital here can help me," he said. "Listen carefully, there's a few things you need to know."

Despite my protests, he spoke, and I finally gave in and listened. He continued talking as dusk turned to night, and the desert sands cooled, and I learnt many things.

"The base will be constructed in 1955," he said. "Eight years after Roswell."

"Roswell?" I rolled my eyes and ignored Gershon's use of tense for the moment. Soon I would learn a new way of thinking about time. About cause and effect.

"You must know the story. In July 1947 something crashed in Roswell, New Mexico."

I nodded, though it hurt like hell.

"Roswell is the only documented case where the government ever claimed to have found a flying saucer." He caught the frank disbelief in my expression but pressed on. "An intel officer from the 509th, one of the first on the scene, said that an object had crashed onto a farm, that it had been recovered and shipped away. It made the front page of the New York Times but the headlines didn't last too long. The 509th was a special unit. Heard of it?"

"Can't say that I have," I replied.

"They saw some interesting action in the war. I'm talking about Hiroshima, Nagasaki. They were the only unit in the world capable of delivering an A-bomb. And then this thing crashed in their backyard. Anyway, the official story was revised to state that it had been a weather balloon, of all things, that had crashed."

"Was it?" I asked.

"You saw what it was."

"The machine? The thing Jenkins called the carapace?"

"No." Gershon coughed. "It was the thing you saw behind the carapace."

The partially dismantled object, seared and sliced.

"That's what they found?"

He paused, wiped phlegm from his lips, and tried to find a more comfortable position. I took off my gown and wrapped it around him.

"What was it?" I asked.

He looked at me wide-eyed. I supposed then that I could admit what it was. I just couldn't say the words.

"It was a time machine, Jon," he said.

While he spoke I fashioned a dressing from strips of his torn theater gown, which he pressed firmly against his abdomen. "Where, when did it come from?"

"No one was sure. One of the project's top consultants said that though most of the working parts could be assembled with current technology, it's impossible to imagine how such a design might have been conceived in the first place." Gershon shrugged. "As to where it was from, all I can say is that the operating interface communicates in English."