There was no sense to the note. There was no sense to anything that Vic Butler did, for that matter. Where he hid away his vast scientific knowledge in that rattle-brained, red-haired head of his has always been a mystery to me. The note read:

Dear Pete:
If you get this, I’m in a jam that promises some action.
Drive out, if plane-peddling is palling on you, and bust into
the lab. I’m leaving another note there for you, old son, and
after you read it you can let your conscience be your guide.
Bring a gat along, and plenty of ammo. Hope’s away, at Aunt
Cleo’s, so don’t get in touch with her and spoil her visit.
Vic

I had a hot prospect lined up for a demonstration that morning, but I didn’t even stop to give him a ring. Vic and I had been buddies ever since we were kids--and, besides, he was Hope’s brother.

Vic’s place was out on the river, about ten miles from town, and that little tan roadster of mine made it in just about ten minutes. The traffic in the business district slowed me up a bit.

There was nothing at all pretentious about the place; it was a rambling, lazy-looking house built largely of native stone, stretching its length comfortably in the shade of the big maples. Perrin, Vic’s man-of-all-work, came hurrying out of the house to greet me as I locked my wheels on the drive before the door.

“I’m glad you’re here, sir!” he exclaimed breathlessly. “I was just about to phone for the police; I was for certain, sir. Such goings on, I don’t know what to think!”

“What’s the matter, Perrin? Where’s Mr. Butler?”

“That’s it, sir! That’s exactly it. Where’s Mr. Butler? And--”

“Just a moment, please! Cut it short, Perrin. What’s happened?”

“I don’t know. Yesterday afternoon Mr. Butler leaves a letter for me, which I’m to mail early this morning, special delivery. It’s to you. I reckon you got it, sir?”

“That’s why I’m here. Go on.”

“Well, after that, he locks himself up in his workroom, so Mrs. Perrin says, she being housekeeper, as you know, sir, leaving word not to disturb him for dinner.

“We don’t think so much of that, Mr. Butler being took with streaks of working at all hours, as you know. But when Miss Hope came home unexpected this morning--”

“What?”

“She cut her visit a few days short, her aunt having other house guests turn up unexpected like, and Miss Hope arrives first thing this morning, being here when I return from town after mailing the letter to you, sir.

“Mrs. Perrin had just told her about the master, and Miss Hope looks into his room. He isn’t there, and the bed hasn’t been slept in. ‘The poor dear, ‘ she says, ‘he’s worked himself half to death, and dropped off on that horrible cot he keeps in his laboratory, ‘ says Miss Hope. ‘I’ll let him sleep.’

“But just a few minutes ago, just before you arrived, sir, she became nervous like, and rapped on the door. There wasn’t a sound. So she went up to the master’s room and found a key, and went in. And now she don’t answer, and we were just about ready to call the police!”

“Let’s go inside!” I hurried by Perrin and through the cool, quiet hall to the broad door that opened into the big room at the back of the house, which was Vic’s laboratory.

“Vic! Hope!” I pounded as hard as I could, shouting their names. There was no response.

“Is there another key, Perrin?” I snapped.

“No, sir; none that I know of. The master was mighty fussy about his workroom.”

“Can we get in through the windows?”

“No. They’re barred, if you remember rightly, and fitted with this frosted glass, so you can’t see in, even.”

“Then get me an ax!” I commanded. “Quick!”

“An ax?” hesitated Perrin.

“An ax--and be quick about it!”

Perrin mumbled a protest and hurried away. I turned to Mrs. Perrin, who had come up to determine the result of my shouting.

“How long is it since Miss Hope went in there?”

“How long, sir? I’d say about twenty minutes before you came. Maybe twenty-five. I wasn’t paying any particular attention, sir. She just got the key and went in. After a few minutes I heard something buzzing in there, and I thought maybe Mr. Butler was showing her some new gadget of his, like he was always doing. Then there was a telephone call for him, and I couldn’t make neither of them answer; that’s when Mr. Perrin and I began to get worried.”

“I see.” Perrin came hurrying up with the ax, and I motioned them aside. I swung the ax, and the head of the weapon crashed against the lock. The knob dropped to the floor with a clatter, but the door gave not at all.

I brought the ax down again, and something cracked sharply. The third blow sent the door swinging wide.

Cautiously, fearing I know not what, I entered the familiar room. Nothing, apparently, had been disturbed. There was no sign of disorder anywhere. The blankets on the narrow cot in the corner of the room had not been unfolded.

But neither Vic nor Hope were anywhere in sight.

“You and Mrs. Perrin stay there by the door,” I suggested. “I don’t know what’s wrong here, but something’s happened. There’s no need for all of us entering.”

My second glance around the room was more deliberate. To my right were the big generators and the switchboards, gleaming with copper bus-bar, and intricate with their tortuous wiring. Directly before me was the long work-bench that ran the full length of the room, littered with a dozen set-ups for as many experiments. At my left was a sizable piece of apparatus that was strange to me; on a small enameled table beside it was a rather large sheet of paper, weighted down with a cracked Florence flask.

In a sort of panic, I snatched up the paper. Vic had said in his note, that he would leave another note for me here. This was it, for in a bold scrawl at the top was my name. And in hardly decipherable script, below, was his message:

Dear Pete:
First of all, let me say that you’ve no particular call to do
anything about this. If I’m in a jam, it’s my own doing, and
due to my bull-headedness, of which you have so often reminded
me.
Knowing your dislike for science other than that related to
aeronautics, I’ll cut this pretty short. It’ll probably sound
crazy to you, anyway.
You know that there’s sound above the frequencies to which the
human ear will respond. You know there are light rays that the
human eyes can’t perceive. Some work I’ve been doing the last
five or six months indicates that there’s a form of life about
us, all around us, which isn’t perceptible to our
senses--which doesn’t mean that it doesn’t exist.
Well, I’m going to do a little exploring. I’m going to take a
whirl at what I’ll call the Infra-Median existence. What I’ll
find there, I don’t know. Life of some kind, however, for my
experiments prove that. Possibly not friendly.
All this being so, there’s an off chance that I’ll find myself
tangled with something I can’t anticipate. And if you are
called upon to read this, then something has gone wrong with
my plans.
Should you wish to take a flier after me, stand in the center
of the square outlined by the four uprights of the device
beside which this little table stands. Be sure your weapon--I
told you to bring a gat--is on your person.
There’s a small instrument board set on one of the posts. Turn
the upper of the two dials until the hand of the meter beside
it moves up to 2700 exactly. Wait a moment, until you’re sure
you have the exact reading. Then turn the second dial until
the two red lines coincide, and as you do so, mark the time.
The thing is set to operate the reverse cycle at three-hour
intervals exactly. When you come down, you’ll start a new
cycle, and it might be important for us to know at just what
minute we can get back to our own plane.
If you decide to try it, tell Perrin to do nothing for at
least a week. If the law started experimenting on this
equipment, we never could climb back. And leave word with them
for Hope; tell her I’ll scramble out somehow--that we will,
if you decide to try your luck.
Vic

Underneath, in Hope’s clear, purposeful hand, was this:

Peter dear:

Not knowing when you’ll arrive, I’m going on ahead. We must
give Vic a hand--mustn’t we?
H.

Naturally, I didn’t understand Vic’s jargon about frequencies and light-rays, for I thought more about football than physics in college, but two things were clear to me. One was that Vic had plunged into some sort of wild experiment, and the other was that Hope had followed him. The rest didn’t matter very much.

“Perrin! Mr. Butler and Miss Hope are safe. Everything is explained in this note. You and Mrs. Perrin are to leave me here, and not disturb anything. Do nothing at all for at least a week. If we aren’t all back here before that time ... take any action you see fit. Understand?”

“No-no, sir. Where--”

“You understand the orders, anyway. That’s all that’s necessary. Close the door--and keep it closed at least a week!” I glared at him, and Perrin closed the door.

The apparatus Vic had mentioned was my first thought. It consisted primarily of four tall, slim posts, set in the form of a square, about a yard apart, and supported by heavy copper brackets mounted on a thick base of insulating material, and each post bore at its top, like a stalk with a single drooping flower, a deep, highly polished reflector, pointing inward and downward. The whole effect was not unlike the skeleton of a miniature skyscraper.

I strode between two of the high, slim black pillars and glanced upward. All four of the reflectors seemed pointed directly at my face, and I could see that each held, not the bulb I had expected, but a crudely shaped blob of fused quartz.

There was nothing to be gained by examining the peculiar machine, and therefore the one quick glance sufficed. If Vic and Hope had gone this route, I was anxious to follow. I glanced down at the papers in my hand, and slowly turned the first dial on the little instrument board, narrowly watching the hand of the meter beside it, as Vic had instructed.

The hand moved slowly, like the hand of an oil-gauge in which the pressure is gradually built up. Twenty-one ... twenty-five ... twenty-six... twenty-seven.

I waited a moment, conscious only of the faint hum of a generator at the other end of the room, and the quivering hand of the meter. I turned the dial back an imperceptible degree, and the hand steadied down exactly upon the numerals “2700.” Then I touched the next dial.

This second dial was no more than a thin disk of hard rubber or bakelite, with a red scratch-mark on one side. On the panel itself, far to the right of the dial’s zero point, was the red scratch-mark that matched it. When the two coincided--well, something happened.

I was conscious of a faint glow from above as I moved the dial slowly, so that its red mark approached the stationary one upon the panel. I glanced up swiftly.

Each of the little blobs of quartz was glowing; each with a light of different color. One was a rich amber, one a pale green, one a vivid, electric blue, and one was fiery red. The intensity of the light increased steadily as I moved the dial.

I could not only see the light; I could feel it. It beat upon my body; throbbed all around me. I had a feeling that the mingling rays of light conflicted with each other.

It seemed to me for a moment that I was growing as light as air; that my feet were drifting off the floor, and then, as the red line of the dial came closer to the indicated point, the feeling left, and I suddenly seemed very heavy. I could hardly support my own weight; my legs were trembling with the burden; sweat broke out over my whole body; the rays of light beat down upon me fiercely, overpoweringly...

Desperately, I quickly turned the dial until the two red marks coincided. A great weight, soft and enveloping, seemed to drop upon me. The senses of sight and hearing and feeling all left me. I could only think--and my thoughts were horrible.

Then, suddenly, there was a terrific crash of sound, and my senses returned.

I looked around. It seemed that an instant before I had been standing there in Vic’s laboratory, slowly turning the second of the two dials, while the four lights beat down upon my body. And now ... and now I was standing in the open, on another world. A nightmare world that words seem inadequate to describe.

The sky was an angry, sulphurous green, pressing low upon a country utterly flat and nearly barren. The only sign of vegetation I could perceive were strange growths that remotely resembled trees--inverted trees, with wide-spreading branches hungrily nursing the black and barren soil, and gnarled, brief roots reaching out tortured arms toward the forbidding sky.

To my left, and some distance away, a vast number of blunt and ugly towers rose against the sinister skyline, but no form of animal life seemed in evidence. Wonderingly, my head whirling, whether from my strange experience or from the shock of finding myself in what was obviously another world, I do not know, I turned toward the city. And as I took my first step, there materialized suddenly out of the thin and ill-smelling air, the figures of perhaps a dozen monstrous creatures.

They were, in effect, men. That is, they had a head, a torso, two arms and two legs apiece. But they were not human. Those huge round eyes, unblinking and browless, were not human, nor were their slitted, sunken mouths. They were not human beings; they were images of despair.

Their thin legs seemed to buckle at the knees, their arms drooped from their shoulders, their mouths sagged at the corners, even their huge ears hung down like a hound’s. Their round, dark eyes, deeply recessed, were caverns of despair.

They were clothed in some coarse, black stuff that bristled as though loosely woven of stiff hair, and yet which was not a true fabric, for it seemed to move within itself, and scintillate, as though composed of billions of restless motes. And as the strange creatures closed in quickly, I saw that theirs was not solid flesh, but, like the clothing that partially covered them, an attenuated substance that was not quite real.

Have you ever sat close to the screen in a motion picture theatre, so that the graininess of the moving film was visible? These creatures were like such shadows, seen in three dimensions.

I retreated two or three swift steps, jerking the revolver from my pocket.

“Back!” I warned, hoping they would understand the tone of voice if not the words. “Back--or I’ll pot a couple of you!”

They glanced at each other, swiftly, almost as though they understood. It seemed to me that their mouths lifted; that they almost smiled. Then they rushed at me.

I had only one box of cartridges, besides those in the cylinder of my gun. I didn’t know what might be in store for me, and I took no chances.

My first shot sent one of the creatures spinning to the ground. Two more were almost upon me before I could level the weapon and pull the trigger again. I got them both.

The rest of that unholy crew were grinning, and their eyes were shining with anticipation. They closed in upon me eagerly, each apparently doing everything in his power to invite my attention. It was bewildering, and I watched them warily, suspecting a trick. There were only three more cartridges left in my gun, and I did not dare replace the fired shells for fear they would rush me when the action was open and the gun momentarily useless.

I was just about to risk one more cartridge when another figure materialized in the ranks of the enemy; a taller, commanding figure, with a shining jewel, perhaps a mark of authority, dangling from his corded brown throat.

The others fell back instantly, and the newcomer approached me swiftly, holding out his hands as though in supplication.

So I was to receive a cordial welcome after all! I breathed a sigh of relief, and pocketed the weapon--and instantly the dark eyes flashed angrily. I held out both hands, to show that they were empty, trying to express my willingness to be friends.

He hesitated, and then uttered a high-pitched sound that I presumed to be a word of command. Before I could free the gun again, the creatures had me, and while their flesh looked more unnatural and unreal than ever, at close range, their long fingers gripped me like talons of steel. The being which had uttered the command disappeared, and my captors led me, struggling and protesting, toward the black, ugly towers of the city.

Over the barren, rocky ground we hurried; past the wretched hovels on the outskirts of the city, and through crooked, dismal streets, toward the center of the city.

A great crowd of creatures similar to my captors hemmed us in. Before us, they thinned into nothingness as we approached, only to swarm into being in some other spot. It was terrifying; an unbelievable experience that made me question my sanity. The only vestige of comfort left me was the hope that they were taking me to Hope and Vic.

At the entrance of one of the huge misshapen black buildings, the creature with the brilliant stone at his throat appeared as suddenly as a light flashes up in the darkness. With him were two others, each wearing a similar jewel of authority. They stood aside for us to enter, and then followed us down a long corridor which was not lighted by any device I could discern, and yet which was not dark.

A broad door swung open, and I was thrust through the doorway.

“Pete!” shouted a familiar voice, and I scrambled to my feet. There was Vic, his red hair tousled, and his face gray with worry. Behind him, her big blue eyes brimming, her lips quivering, was Hope.

“Vic! Well, here I am. And Hope, dear...”

My voice trailed off. These were not Vic and Hope before me; they were unreal creatures, like the beings which had captured me. I could recognize the face and the figure of the woman I loved and of her brother; but they seemed to have no substance.

Hope suddenly put her arms about me. She was sobbing.

“Don’t, Peter!” she whispered.

“Don’t look at me like that. I know how you feel. You--you and Vic--you aren’t real to me, either! We’re just shadows--lost souls...”

“Buck up, Hope!” Vic’s voice was kindly, yet firm and gravely commanding. “We’re all right. Only--temporarily--we’re Infra-Medians. Sit down, Pete, and let’s talk. It may be that there’s no time to lose in making some plans.”