There wasn't that much time."

Monk ran a hand through his short pig-bristle hair, and ended the gesture by scratching the back of his head violently.

"He wasn't an invisible man," he said. "He was just intangible."

"Anyone who pa.s.sed me was invisible!" the stewardess snapped.

They walked back into the plane cabin where Gail Adams waited tight-lipped in her seat. Monk glanced down at Mr. Morand in pa.s.sing, remarked, "If it wouldn't get me measured for a straight jacket, I'd almost say our friend of the abbreviated words begins to look like an authority on the little man who wasn't there."

Doc Savage pa.s.sed on to the pilot's compartment. He introduced himself. He told the pilot, briefly, that a murder attempt had been made on one of the pa.s.sengers and the a.s.sailant had fled aft in the plane-but couldn't be found."Could he have parachuted-he may have had a chute along-without your being aware?" Doc finished.

Pilot and co-pilot shook their heads instantly. It was impossible. The trim of the ship would have been upset. They'd have noticed instantly. Further than that, there was a warning light which showed on the instrument panel, showed a bright red, when any door was open. The light hadn't shone red.

"I want the functioning of that light tested when we land," Doc said. "If there's any doubt about my authority to request such a test, consult your operational vice-president."

"Yes, sir," said the puzzled captain. "I don't question your authority, sir. I happen to know you own a considerable interest in the airline."

"Another thing," Doc said. "I want you personally to examine the tail section. I suggest you do it because I've told you what happened, but if you'd prefer to do so, select a trustworthy mechanic to remove the bulkhead screws and search the rear end."

"Yes, sir."

"How about your elevator trim tab the last half hour? Had to change it much? A man, even a small one, going into the tail-section would shift the center of gravity and you would have to re-trim."

The mate said uncertainly, "The air is rough. We've had to change the tab a few times after tr.i.m.m.i.n.g out of the climb to level flight."

But the first officer was more positive. "We haven't needed to change the tab that much."

"You think, then, that a man couldn't be hiding in the rearmost section of the fuselage?" Doc asked.

"Sir, I'm positive he couldn't be," the first officer declared.

"Make a search at the end of the trip anyway."

"Yes, sir."

Monk had guessed the purpose of Doc's trip to the control compartment, and he asked, "They have to trim out for him? I hadn't thought of that."

"The pilot says not."

"I don't get it."

"It's interesting, all right."

Monk said he didn't think interesting was the word. He tried to think of a word. He ended by producing a shudder that seemed to surprise himself.

"But there was a man!" Gail gasped.

"There seems to be some evidence to the contrary," Doc told her dryly. "However, we saw him as clearly as you did."

Gail pointed at Mr. Morand, "Then he-his mind wasn't bereft-when he said we'd discover the fellow wasn't here."

"His prediction was accurate, anyway," Doc admitted. "Now Miss Adams, this mustn't throw you. Themore utterly impossible a thing seems, the more blatant the trickery, usually." He consulted his watch.

"We have nearly an hour longer before we reach New York. Suppose you give me a very complete picture of the situation back home."

Gail nodded, for she was eager to talk. She discovered that Doc Savage was interested in her own background, and in Dan's. So she told him that they had been born on a Kansas farm, that there was two years difference in their age, and that her brother had always been interested in electricity, or electronics as it had come to be called. She told him a great deal about Dan-that Dan liked fishing and hunting, and wasn't much of a hand for girls, although he liked to give the impression he was quite a wolf, by whistling at them on the street.

"My brother hadn't grown up, really, Mr. Savage," Gail explained. "He was quite skilled in radar work, but rather underdeveloped in other ways."

"What do you mean by underdeveloped?" Doc Savage asked.

"Oh, Dan didn't have too good judgment, and I had to sort of look after him to keep him out of trouble.

Nothing serious, you understand. Dan never came near doing anything really bad." She hesitated, nipping at her lips with her teeth. Then she said reluctantly, "Except once, that is. Dan was almost involved with some other young fellows in a plot to take a car. But I found out about it, and put a stop to it."

"You mean steal a car."

"I-yes. But he didn't, of course. And probably he wouldn't have, anyway, even if I hadn't interfered."

"When was this incident?"

"Oh, several years ago."

The rest of Gail's story included the fact that her parents had pa.s.sed away, her mother five years ago and her father three years before, and she and Dan had been living in the southern coast city two years, or since the inception of the radar experimental work. To Doc's questions, she replied that Dan had no known enemies, and hadn't seemed any different lately than usual. However, she amended this to: "But it was hard to tell about Dan. He had an effervescent nature, always pranking, and you couldn't tell much about him."

"Even you, as Dan's sister, couldn't tell much about him?"

"That's right." Suddenly tears came to her eyes, and she lowered her head. "Don't get the idea that I didn't love my brother. I did. He meant a great deal to me. I've always taken care of him, and losing him is a terrible shock." She began shaking with sobs.

The sun finally lifted above a strata of ground fog that overlay the mountain area of eastern Pennsylvania, and laid its light redly against the long glittering blades of the airliner wings. There was, far ahead, a vague mushroom of industrial haze, and New York City would lie under this.

Presently Gail's sobbing ended in grim self-control, and Doc Savage put several questions. His casual tone belied the importance of the queries: Had Dan mentioned any recent fear? Had he seen anything odd in the radar scope before? Was Dan inclined to be imaginative? Had he ever been the patient of a psychiatrist? Had Gail ever seen Mr. Morand before yesterday? Did she think Dan had met him before?

Was she positive Dan had no insurance with Mr. Morand's company, if he had a company?

To all of these questions, Gail shook her head numbly. This seemed a sufficient answer to satisfy Doc.The plane made the sweep south now over Staten Island. Bedloe with the Statue of Liberty moved under Gail's intent staring eyes, and at first she did not realize what it was. The Statue of Liberty-New York-she thought. She had never been in New York, and she recognized the skyline of Manhattan Island readily from the many pictures she'd seen, although from the air it hardly resembled a skyline. The city seemed distant, compact and smaller than she had imagined. She supposed that one shouldn't arrive in New York City for the first time by air, for the most impressive effect.

La Guardia Field seemed smaller than she had expected. But, when the plane had taxied to the disembarking sheds, and she was outside, moving down the steps preceded by Monk Mayfair and followed closely by Doc Savage-Doc carrying Mr. Morand easily-she began to get her perspective back. New York was going to be a large city, after all.

An official of the airline met them. An anxious man, almost wringing his hands. He was concerned about what had happened-evidently the pilot had radioed ahead-and anxious to be of service. Doc Savage gave him pleasantly vague answers and a.s.surances that the airline was nowhere at fault.

Gail noticed Doc watching the plane. The pilot was now taxiing it toward the hangars, some distance away, where the airline maintenance was done.

Doc then said, "Will you excuse me?" and gave the limp Mr. Morand to Monk to hold. Doc turned and left quickly. . . . He was not gone long, however-four or five minutes, perhaps-and then was back.

He told the airline official, "We'd like a place to wait in privacy, until our friend here regains consciousness."

They were shown to a small office that had been hastily cleared of its occupants. It was warm there.

Gail's cheeks felt numb under her fingers, and she was sure there were tiny shot-like snowflakes in the air outdoors. No sunlight fell into the room, and the skies were leaden.

Now Doc Savage and Monk Mayfair had a conversation, using a language Gail had never heard before-a guttural tongue, not particularly musical, but not unpleasant either. She listened wonderingly.

She had studied French, Spanish and a little Esperanto, but this bore no relation to any of these tongues, nor to anything she had heard before.

Monk was grinning wryly at the end, and she asked him, "What language were you speaking?"

"Mayan," he told her.

"Mayan?" Gail was puzzled. "That's South American, isn't it? Or Central American?"

"Central America," Monk agreed. "This is the original primitive lingo." Monk went over and scowled at Mr. Morand. They had put him in a swivel chair. "He should be making his debut by now. That stuff never knocks them over an hour and a half," Monk said, pushing Mr. Morand's head back.

Mr. Morand's eyes remained closed. His color was good, though. His hands, which hung limp, looked brown enough to be wearing leather gloves.

"What do you think became of the man who tried to kill me?" Gail asked.

"According to slumber-boy, here, he wasn't there," Monk said.

"Do you believe that?"

"When I do, you can send for the fellows with the white coats," Monk said."Where did you learn to speak primitive Mayan?" Gail asked.

"Oh, we've been down there a time or two." Monk went over and looked from the window. "That pilot should be showing up. It isn't an all-morning job to search the tail of the plane."

About five minutes later, the pilot arrived. "There wasn't anyone," he said. "There wasn't a soul hidden in the tail-section."

"So the little man who wasn't there," Monk said blankly, "really wasn't there!"

Chapter VI.

GAIL couldn't believe it. A man had tried to kill her; she was sure of that. Seemingly he had disappeared into thin air aboard the plane. It was impossible. She sank into a chair, hands clenched, thinking in wild terror of the way her brother and Cooper had died, hanged from a support that wasn't there, either. And in locked rooms.

Before she could pry any words from her fright, another man arrived.

"h.e.l.lo, Doc," he said. "I been looking all over for you. They told me at the airline desk that you were here."

Doc introduced the newcomer. "This is Ham Brooks, one of our a.s.sociates. He flew the plane that took us to intercept you, Gail. Then he brought the plane back."

Ham Brooks was, Gail's first thought ran, ridiculously dapper. He was decked out, of all things, in a morning outfit-striped trousers, dark swag coat and fawn lap-over vest. Like a diplomat for a formal day affair.

"This," said Ham Brooks, seizing Gail's hand, "Is a pleasant surprise. You're not forty-five years old, you don't weigh two hundred pounds, and you haven't got a moustache."

"Where on earth did you get that description?" Gail gasped.

Ham Brooks indicated Monk Mayfair. "From my short and hairy-eared co-worker here, the one with the longsuffering wife and thirteen not overly bright children."

"That's a d.a.m.ned lie!" Monk said indignantly. "I'm not married."

"It's no bigger lie than the description you told me she gave of herself over the telephone," Ham advised.

The pair glowered at each other, and Doc Savage, looking somewhat irritated, told Ham, "You'd better hangar the plane, and we'll meet you later downtown."

Ham told Monk something. He used the Mayan dialect that Doc and Monk had employed earlier. Monk jumped, made his hands into fists, and yelled, "That's an insult only a shyster lawyer would think up!"

Ham went out chuckling. And presently the pilot of the plane also departed, after receiving Doc's thanks for his search of the plane.Monk, still scowling, eased over beside Mr. Morand's chair. He suddenly sent out a hand, and tipped the chair over backward. Mr. Morand, as the feeling of falling got at him unexpectedly, instinctively threw out his hands.

"Why, you deceitful little ghost-raiser!" Monk said grimly. "You've been conscious for some time!"

Mr. Morand, peering at Monk with alarm, hastily scrambled to his feet. "Don't you touch me!" he gasped. "Don't you dare!" Then he demanded wildly, "What happened to me? Where am I? I slept?

Why?"

"Don't you know a fainting spell when you have one?" Monk asked him.

"Faint? No! No, never!" Mr. Morand seemed deeply frightened. "No! Not susceptible. Never faint. . . .

Beset! Was beset! Inhabited!"

"So you're inhabited," Monk said. "And you're not accustomed to fainting. I supposed you're more fully accustomed to seeing little men who aren't there."

Mr. Morand jerked visibly. His cone of white hair seemed to get an inch taller. He staggered to a chair, collapsed in it, wailing. "My G.o.d! I remember! Oh! I remember!" He clamped his fingers to his cheeks, and the brown leather fingers drew the brown leather cheeks out of shape. "You searched? Find him?

Did you?" The words were as distorted as his face.

"What do you think?" Monk asked.

"Seek!" Morand gasped. "Seek everywhere! Miss nothing. Hunt thoroughly. Please!"

Monk glanced at Doc Savage, who remained expressionlessly attentive. So Monk told Morand, "Pal, we went over that plane like monkeys after a peanut. . . . And you seem to have a good idea what we found. Now we're waiting for you to tell us why."

"Tell what? I know nothing?"

"Watch out, you used three words in a row. . . . Friend, you said we wouldn't find that guy. I know you said it just as clearly as I know I saw the fellow. Now, where'd he go?"

Morand bent forward, fingers working hard at his face again. "Back," he wailed. "Back. Evil. Evil returneth."

Monk glanced at Doc again, and suggested, "I don't think he's wound up enough. I think a good arm-twisting might wind him up so that more words would come out at a time. And maybe some truth."

Morand straightened. "Truth? You wish it? Really?"

"We hanker. Strongly," Monk said.