ommander Stone, grizzled chief of the Planetary Exploration Forces, acknowledged Captain Brand Bowen's salute and beckoned him to take a seat.

Brand, youngest officer of the division to wear the triple-V for distinguished service, sat down and stared curiously at his superior. He hadn't the remotest idea why he had been recalled from leave: but that it was on a matter of some importance he was sure. He hunched his big shoulders and awaited orders.

"Captain Bowen," said Stone. "I want you to go to Jupiter as soon as you can arrange to do so, fly low over the red area in the southern hemisphere, and come back here with some sort of report as to what's wrong with that infernal death spot."

He tapped his radio stylus thoughtfully against the edge of his desk.

"As you perhaps know, I detailed a ship to explore the red spot about a year ago. It never came back. I sent another ship, with two good men in it, to check up on the disappearance of the first. That ship, too, never came back. Almost with the second of its arrival at the edge of the red area all radio communication with it was cut off. It was never heard from again. Two weeks ago I sent Journeyman there. Now he has been swallowed up in a mysterious silence."

An exclamation burst from Brand's lips. Sub-Commander Journeyman! Senior officer under Stone, ablest man in the expeditionary forces, and Brand's oldest friend!

Stone nodded comprehension of the stricken look on Brand's face. "I know how friendly you two were," he said soberly. "That's why I chose you to go and find out, if you can, what happened to him and the other two ships."

Brand's chin sank to rest on the stiff high collar of his uniform.

"Journeyman!" he mused. "Why, he was like an older brother to me. And now ... he's gone."

here was silence in Commander Stone's sanctum for a time. Then Brand raised his head.

"Did you have any radio reports at all from any of the three ships concerning the nature of the red spot?" he inquired.

"None that gave definite information," replied Stone. "From each of the three ships we received reports right up to the instant when the red area was approached. From each of the three came a vague description of the peculiarity of the ground ahead of them: it seems to glitter with a queer metallic sheen. Then, from each of the three, as they passed over the boundary—nothing! All radio communication ceased as abruptly as though they'd been stricken dead."

He stared at Brand. "That's all I can tell you, little enough, God knows. Something ominous and strange is contained in that red spot: but what its nature may be, we cannot even guess. I want you to go there and find out."

Brand's determined jaw jutted out, and his lips thinned to a purposeful line. He stood to attention.

"I'll be leaving to-night, sir. Or sooner if you like. I could go this afternoon: in an hour—"

"To-night is soon enough," said Stone with a smile. "Now, who do you want to accompany you?"

Brand thought a moment. On so long a journey as a trip to Jupiter there was only room in a space ship—what with supplies and all—for one other man. It behooved him to pick his companion carefully.

"I'd like Dex Harlow," he said at last. "He's been to Jupiter before, working with me in plotting the northern hemisphere. He's a good man."

"He is," agreed Stone, nodding approval of Brand's choice. "I'll have him report to you at once."

He rose and held out his hand. "I'm relying on you, Captain Bowen," he said. "I won't give any direct orders: use your own discretion. But I would advise you not to try to land in the red area. Simply fly low over it, and see what you can discern from the air. Good-by, and good luck."

Brand saluted, and went out, to go to his own quarters and make the few preparations necessary for his sudden emergency flight.

he work of exploring the planets that swung with Earth around the sun was still a new branch of the service. Less than ten years ago, it had been, when Ansen devised his first crude atomic motor.

At once, with the introduction of this tremendous new motive power, men had begun to build space ships and explore the sky. And, as so often happens with a new invention, the thing had grown rather beyond itself.

Everywhere amateur space flyers launched forth into the heavens to try their new celestial wings. Everywhere young and old enthusiasts set Ansen motors into clumsily insulated shells and started for Mars or the moon or Venus.

The resultant loss of life, as might have been foreseen, was appalling. Eager but inexperienced explorers edged over onto the wrong side of Mercury and were burned to cinders. They set forth in ships that were badly insulated, and froze in the absolute zero of space. They learned the atomic motor controls too hastily, ran out of supplies or lost their courses, and wandered far out into space—stiff corpses in coffins that were to be buried only in time's infinity.

To stop the foolish waste of life, the Earth Government stepped in. It was decreed that no space ship might be owned or built privately. It was further decreed that those who felt an urge to explore must join the regular service and do so under efficient supervision. And there was created the Government bureau designated as the Planetary Exploration Control Board, which was headed by Commander Stone.

nder this Board the exploration of the planets was undertaken methodically and efficiently, with a minimum of lives sacrificed.

Mercury was charted, tested for essential minerals, and found to be a valueless rock heap too near the sun to support life.

Venus was visited and explored segment by segment; and friendly relations were established with the rather stupid but peaceable people found there.

Mars was mapped. Here the explorers had lingered a long time: and all over this planet's surface were found remnants of a vast and intricate civilization—from the canals that laced its surface, to great cities with mighty buildings still standing. But of life there was none. The atmosphere was too rare to support it; and the theory was that it had constantly thinned through thousands of years till the last Martian had gasped and died in air too attenuated to support life even in creatures that must have grown greater and greater chested in eons of adaptation.

Then Jupiter had been reached: and here the methodical planet by planet work promised to be checked for a long time to come. Jupiter, with its mighty surface area, was going to take some exploring! It would be years before it could be plotted even superficially.

rand had been to Jupiter on four different trips; and, as he walked toward his quarters from Stone's office, he reviewed what he had learned on those trips.

Jupiter, as he knew it, was a vast globe of vague horror and sharp contrasts.

Distant from the sun as it was, it received little solar heat. But, with so great a mass, it had cooled off much more slowly than any of the other planets known, and had immense internal heat. This meant that the air—which closely approximated Earth's air in density—was cool a few hundred yards up from the surface of the planet, and dankly hot close to the ground. The result, as the cold air constantly sank into the warm, was a thick steamy blanket of fog that covered everything perpetually.

Because of the recent cooling, life was not far advanced on Jupiter. Too short a time ago the sphere had been but a blazing mass. Tropical marshes prevailed, crisscrossed by mighty rivers at warmer than blood heat. Giant, hideous fernlike growths crowded one another in an everlasting jungle. And among the distorted trees, from the blanket of soft white fog that hid all from sight, could be heard constantly an ear-splitting chorus of screams and bellows and whistling snarls. It made the blood run cold just to listen—and to speculate on what gigantic but tiny-brained monsters made them.

Now and then, when Brand had been flying dangerously low over the surface, a wind had risen strong enough to dispel the fog banks for an instant; and he had caught a flash of Jovian life. Just a flash, for example, of a monstrous lizard-like thing too great to support its own bulk: or a creature all neck and tail, with ridges of scale on its armored hide and a small serpentine head weaving back and forth among the jungle growths.

ccasionally he had landed—always staying close to the space ship, for Jupiter's gravity made movement a slow and laborious process, and he didn't want to be caught too far from security. At such times he might hear a crashing and splashing and see a reptilian head loom gigantically at him through the fog. Then he would discharge the deadly explosive gun which was Earth's latest weapon, and the creature would crash to the ground. The chorus of hissings and bellowings would increase as he hastened slowly and laboriously back to the ship, indicating that other unseen monsters of the steamy jungle had flocked to tear the dead giant to pieces and bolt it down.

Oh, Jupiter was a nice planet! mused Brand. A sweet place—if one happened to be a two-hundred-foot snake or something!

He had always thought the entire globe was in that new, raw, marshy state. But he had worked only in one comparatively small area of the northern hemisphere; had never been within thirty thousand miles of the red spot. What might lie in that ominous crimson patch, he could not even guess. However, he reflected, he was soon to find out, though he might never live to tell about it.

Shrugging his shoulders, he turned into the fifty story building in which was his modest apartment. There he found, written by the automatic stylus on his radio pad, the message: "Be with you at seven o'clock. Best regards, and I hope you strangle. Dex Harlow."

ex Harlow was a six-foot Senior Lieutenant who had been on many an out-of-the-way exploratory trip. Like Brand he was just under thirty and perpetually thirsting for the bizarre in life. He was a walking document of planetary activity. He was still baked a brick red from a trip to Mercury a year before: he had a scar on his forehead, the result of jumping forty feet one day on the moon when he'd meant to jump only twenty; he was minus a finger which had been irreparably frost-bitten on Mars; and he had a crumpled nose that was the outcome of a brush with a ten-foot bandit on Venus who'd tried to kill him for his explosive gun and supply of glass, dyite-containing cartridges.

He clutched Brand's fingers in a bone-mangling grip, and threw his hat into a far corner.

"You're a fine friend!" he growled cheerfully. "Here I'm having a first rate time for myself, swimming and planing along the Riviera, with two more weeks leave ahead of me—and I get a call from the Old Man to report to you. What excuse have you for your crime?"

"A junket to Jupiter," said Brand. "Would you call that a good excuse?"

"Jupiter!" exclaimed Dex. "Wouldn't you know it? Of course you'd have to pick a spot four hundred million miles away from all that grand swimming I was having!"

"Would you like to go back on leave, and have me choose someone else?" inquired Brand solemnly.

"Well, no," said Dex hastily. "Now that I'm here, I suppose I might as well go through with it."

Brand laughed. "Try and get you out of it! I know your attitude toward a real jaunt. And it's a real jaunt we've got ahead of us, too, old boy. We're going to the red spot. Immediately."

ex's sandy eyebrows shot up. "The red spot! That's where Coblenz and Heiroy were lost!"

"And Journeyman," added Brand. "He's the latest victim of whatever's in the hell-hole."

Dex whistled. "Journeyman too! Well, all I've got to say is that whatever's there must be strong medicine. Journeyman was a damn fine man, and as brave as they come. Have you any idea what it's all about?"

"Not an idea. Nobody has. We're to go and find out—if we can. Are you all ready?"

"All ready," said Dex.

"So am I. We'll start at eleven o'clock in one of the Old Man's best cruisers. Meanwhile, we might as well go and hunt up a dinner somewhere, to fortify us against the synthetic pork chops and bread we'll be swallowing for the next fortnight."

They went out; and at ten minutes of eleven reported at the great space ship hangars north of New York, with their luggage, a conspicuous item of which was a chess board to help while away the long, long days of spacial travel. Brand then paused a little while for a final check-up on directions.

They clambered into the tiny control room and shut the hermetically sealed trap-door. Brand threw the control switch and precisely at eleven o'clock the conical shell of metal shot heavenward, gathering such speed that it was soon invisible to human eyes. He set their course toward the blazing speck that was Jupiter, four hundred million miles away; and then reported their start by radio to Commander Stone's night operator.

The investigatory expedition to the ominous red spot of the giant of the solar system was on.