“It’s okay,” Albert said uncomfortably.

“Albert you are and Albert you shall be from now on,” Robert Jenkins promised. “I started to ask if you’ve ever taken the red-eye before.”

“No. I’ve never even flown across the country before.”

“Well, I have. Many times. On a few occasions I have even gone against my natural inclination and stayed awake for awhile. Mostly when I was a younger man and the flights were noisier. Having said that much, I may as well date myself outrageously by admitting that my first coast-to-coast trip was on a TWA prop-job that made two stops... to refuel.”

“My observation is that very few people go to sleep on such flights during the first hour or so... and then just about everyone goes to sleep. During that first hour, people occupy themselves with looking at the scenery, talking with their spouses or their travelling companions, having a drink or two—”

“Settling in, you mean,” Albert suggested. What Mr Jenkins was saying made perfect sense to him, although he had done precious little settling in himself; he had been so excited about his coming journey and the new life which would be waiting for him that he had hardly slept at all during the last couple of nights. As a result, he had gone out like a light almost as soon as the 767 left the ground.

“Making little nests for themselves,” Jenkins agreed. “Did you happen to notice the drinks trolley outside the cockpit, dea — Albert?”

“I saw it was there,” Albert agreed.

Jenkins’s eyes shone. “Yes indeed — it was either see it or fall over it. But did you really notice it?”

“I guess not, if you saw something I didn’t.”

“It’s not the eye that notices, but the mind, Albert. The trained deductive mind. I’m no Sherlock Holmes, but I did notice that it had just been taken out of the small closet in which it is stored, and that the used glasses from the pre-flight service were still stacked on the bottom shelf. From this I deduce the following: the plane took off uneventfully, it climbed toward its cruising altitude, and the autopilot device was fortunately engaged. Then the captain turned off the seatbelt light. This would all be about thirty minutes into the flight, if I’m reading the signs correctly — about 1:00 A.M., PDT.

When the seatbelt light was turned out, the stewardesses arose and began their first task — cocktails for about one hundred and fifty at about 24,000 feet and rising. The pilot, meanwhile, has programmed the autopilot to level the plane off at 36,000 feet and fly east on heading thus-and-such. A few passengers — eleven of us, in fact — have fallen asleep. Of the rest, some are dozing, perhaps (but not deeply enough to save them from whatever happened), and the rest are all wide awake.”

“Building their nests,” Albert said.

“Exactly! Building their nests!” Jenkins paused and then added, not without some melodrama: “And then it happened!”

“What happened, Mr Jenkins?” Albert asked. “Do you have any ideas about that?”

Jenkins did not answer for a long time, and when he finally did, a lot of the fun had gone out of his voice. Listening to him, Albert understood for the first time that, beneath the slightly theatrical veneer, Robert Jenkins was as frightened as Albert was himself. He found he did not mind this; it made the elderly mystery writer in his running-to-seed sport-coat seem more real.

“The locked-room mystery is the tale of deduction at its most pure,” Jenkins said. “I’ve written a few of them myself — more than a few, to be completely honest — but I never expected to be a part of one.”

Albert looked at him and could think of no reply. He found himself remembering a Sherlock Holmes story called “The Speckled Band.” In that story a poisonous snake had gotten into the famous locked room through a ventilating duct. The immortal Sherlock hadn’t even had to wake up all his brain-cells to solve that one.

But even if the overhead luggage compartments of Flight 29 had been filled with poisonous snakes — stuffed with them — where were the bodies? Where were the bodies? Fear began to creep into him again, seeming to flow up his legs toward his vitals. He reflected that he had never felt less like that famous gunslinger Ace Kaussner in his whole life.

“If it were just the plane,” Jenkins went on softly, “I suppose I could come up with a scenario — it is, after all, how I have been earning my daily bread for the last twenty-five years or so. Would you like to hear one such scenario?”

“Sure,” Albert said.

“Very well. Let us say that some shadowy government organization like The Shop has decided to carry out an experiment, and we are the test subjects. The purpose of such an experiment, given the circumstances, might be to document the effects of severe mental and emotional stress on a number of average Americans. They, the scientists running the experiment, load the airplane’s oxygen system with some sort of odorless hypnotic drug.”

“Are there such things?” Albert asked, fascinated.

“There are indeed,” Jenkins said. “Diazaline, for one. Methoprominol, for another. I remember when readers who liked to think of themselves as ‘serious-minded’ laughed at Sax Rohmer’s Fu Manchu novels. They called them panting melodrama at its most shameful.” Jenkins shook his head slowly. “Now, thanks to biological research and the paranoia of alphabet agencies like the CIA and the DIA, we’re living in a world that could be Sax Rohmer’s worst nightmare.”

“Diazaline, which is actually a nerve gas, would be best. It’s supposed to be very fast. After it is released into the air, everyone falls asleep, except for the pilot, who is breathing uncontaminated air through a mask.”

“But—” Albert began.

Jenkins smiled and raised a hand. “I know what your objection is, Albert, and I can explain it. Allow me?”

Albert nodded.

“The pilot lands the plane — at a secret airstrip in Nevada, let us say. The passengers who were awake when the gas was released — and the stewardesses, of course — are off-loaded by sinister men wearing white Andromeda Strain suits. The passengers who were asleep — you and I among them, my young friend — simply go on sleeping, only a little more deeply than before. The pilot then returns Flight 29 to its proper altitude and heading. He engages the autopilot. As the plane reaches the Rockies, the effects of the gas begin to wear off. Diazaline is a so-called clear drug, one that leaves no appreciable after-effects. No hangover, in other words. Over his intercom, the pilot can hear the little blind girl crying out for her aunt. He knows she will wake the others. The experiment is about to commence. So he gets up and leaves the cockpit, closing the door behind him.”

“How could he do that? There’s no knob on the outside.”

Jenkins waved a dismissive hand. “Simplest thing in the world, Albert. He uses a strip of adhesive tape, sticky side out. Once the door latches from the inside, it’s locked.”

A smile of admiration began to overspread Albert’s face — and then it froze. “In that case, the pilot would be one of us,” he said.

“Yes and no. In my scenario, Albert, the pilot is the pilot. The pilot who just happened to be on board, supposedly deadheading to Boston. The pilot who was sitting in first class, less than thirty feet from the cockpit door, when the manure hit the fan.”

“Captain Engle,” Albert said in a low, horrified voice.

Jenkins replied in the pleased but complacent tone of a geometry professor who has just written QED below the proof of a particularly difficult theorem. “Captain Engle,” he agreed.

Neither of them noticed Crew-Neck looking at them with glittering, feverish eyes. Now Crew-Neck took the in-flight magazine from the seatpocket in front of him, pulled off the cover, and began to tear it in long, slow strips. He let them flutter to the floor, where they joined the shreds of the cocktail napkin around his brown loafers. His lips were moving soundlessly.