Lieutenant Nevsky tried to make his voice crackle with authority as he placed his hand on the butt of his blaster. "What are you men doing here?"

There was a small murmur from the men, but by and large they remained quiet. Eyes turned to the one of them who stood in front, as though they were waiting for him to speak.

The leader of the men was smiling, and his face was crinkled into an expression of apparent good will. His straight hair, parted in the middle, had a light-orange tint to it. His cheekbones were broad and he chewed gum. His clothing was of synthetic fiber, as was true of that of the others, but unlike the others', his shirt and trousers were ornamented with brass buttons that were large and bulky. Four on his shirt front, one each on the two shirt pockets, and four down the side of each pants leg: fourteen altogether. They seemed to serve no purpose; to be only for show.

"All right, Summers," said the lieutenant, turning to this man, "what are the men doing here?"

Summers spoke now in a soft, wheedling voice.

"Well, now, Lieutenant, we thought it would be nice to meet the new man. He'll be seeing a lot of us. He'll be asking questions. Why shouldn't we meet him now?"

He looked at Lucky Starr as he spoke, and for a moment there was a touch of ice in that glance that swallowed up all the show of softness.

The lieutenant said, "You men should be at work."

"Have a heart, Lieutenant," said Summers, chewing even more slowly and leisurely. "We've been working. Now we want to say hello."

The lieutenant was obviously uncertain as to his next move. He looked doubtfully at Lucky.

Lucky said, "Which rooms are to be ours, Lieutenant?"

"Rooms 2A and 2B, sir. To find them-"

''I'l find them. I'm sure one of these men will direct me. And now, Lieutenant Nevsky, that you've directed us to our quarters, I think your assignment is completed. I'll be seeing you again."

"I can't leave!" said Lieutenant Nevsky in a low, appalled whisper.

"I think you can."

"Sure you can, Lieutenant," said Summers, grinning more broadly than ever. "A simple hello won't hurt the boy." There was a snicker of laughter from the men behind him. "And besides, you've been asked to leave."

Bigman approached Lucky and muttered in an urgent whisper. "Lucky, let me give the V-frog to the lieutenant I can't fight and hold it, too."

"You just hold it," said Lucky. "I want it exactly here... Good day, Lieutenant. Dismissed!"

The lieutenant hesitated, and Lucky said in a tone that, for all its softness, bit like steel. "That's an order, Lieutenant."

Lieutenant Nevsky's face assumed a soldierly rigidity. He said sharply, "Yes, sir."

Then, surprisingly, he hesitated one further moment and glanced down at the V-frog in the crook of Big-man's arm, as it chewed idly at a fern frond. "Take care of that little thing." He turned and was in the Agrav corridor in two steps, disappearing almost at once in a rush of speed.

Lucky turned to face the men again. He was under no illusions. They were grim-faced and they meant business, but unless he could face them down and prove that he meant business as well, his mission would come to nothing against the rock of their hostility. He would have to win them over somehow.

Summers' smile had become the least bit wolfish. He said, "Well, now, friend, the uniform-boy is gone. We can talk. Fm Red Summers. What's your name?"

Lucky smiled in return. "My name is David Starr. My friend's name is Bigman."

"Seems to me I heard you called Lucky when all that whispering was going on a while back."

"I'm called Lucky by my friends."

"Isn't that nice. Do you want to stay lucky?"

"Do you know a good way?"

"Matter of fact, Lucky Starr, I do." Suddenly his face contorted itself into a bitter scowl. "Get off Jupiter Nine."

There was a hoarse roar of approval from the others, and a few voices took up the cry of "Get off! Get off!"

They crowded closer, but Lucky stood his ground. "I have important reasons to stay on Jupiter Nine."

"In that case, I'm afraid you aren't lucky," said Summers. "You're a greenhorn and you look soft, and soft greenhorns get hurt on Jupiter Nine. We worry about you."

"I think I won't get hurt."

"That's what you think, eh?" said Summers. "Ar-mand, come here."

From the ranks behind him, a huge man stepped forward, round-faced, beefy of build, with large shoulders and a barrel chest. He topped Lucky's six feet one by half a head and looked down at the young councilman with a smile that showed yellowed, wide-spaced teeth.

The men were beginning to take seats on the floor. They shouted to one another with lighthearted cheer, as though they were about to watch a ball game.

One called out, "Hey, Armand, watch out you don't step on the kid!"

Bigman started, and glared furiously in the direction of the voice but could not identify the speaker.

Summers said, "You could still leave, Starr."

Lucky said, "I have no intention of doing so, particularly at a moment when you seem to be planning some sort of entertainment."

"Not for you," said Summers. "Now listen, Starr, we're ready for you. We've been ready since we got word that you were coming. We've had enough of you little tinhorns from Earth and we aren't taking any more. I've got men stationed on various levels. We'll know if the commander tries to interfere, and if he does, then by Jupiter, we're ready to go on strike. Am I right, men?"

"Right!" came back the multiple roar.

"And the commander knows it," said Summers, "and I don't think he'll interfere. So this gives us our chance to give you our initiation and after that I'll ask you again if you want to leave. If you're conscious, that is."

"You're going to a lot of trouble for nothing," said Lucky. "What harm am I doing you?"

"You won't be doing us any," said Summers. "I guarantee that."

Bigman said, in his tense, high-pitched voice, "Look, you cobber, you're talking to a councilman. Have you stopped to figure what happens if you fool with the Council of Science?"

Summers looked at him suddenly, put his fists on his hips, and bent his head back to laugh. "Hey, men, it talks. I was wondering what it was. It looks as though Lucky Snoop has brought along his baby brother for protection."

Bigman went dead-white, but under the cover of the laughter Lucky stooped and spoke through stiff lips. "Your job is to hang on to the V-frog, Bigman. I'll take care of Summers. And, Great Galaxy, Bigman, stop broadcasting anger! I can't get a thing on the V-frog except that."

Bigman swallowed hard twice, three tunes.

Summers said softly, "Now, Councilman Snoop, can you maneuver under Agrav?"

"I just have, Mr. Summers."

"Well, we'll just have to test you and make sure. We can't have anyone around who hasn't learned all the Agrav ropes. It's too dangerous. Right, men?"

"Right!" they roared again.

"Armand here," said Summers, and his hand rested on one of Armand's huge shoulders, "is our best teacher. You'll know all about Agrav maneuvering when you're through with him. Or you will know if you stay out of his way. I suggest you get out into the Agrav corridor now. Armand will join you."

Lucky said, "If I choose not to go?"

"Then we'll throw you into the corridor anyway and Armand goes after you."

Lucky nodded. "You seem determined. Are there any rules to this lesson I'm going to get?"

There was wild laughter, but Summers held up his arms. "Just keep out of Armand's way, Councilman. That' s the only rule you'll have to remember. We'll be at the lip of the corridor watching. If you try to crawl out of Agrav before you've completed your lesson, we'll throw you back in, and there are men stationed at other levels, watching, and they're ready to do the same."

Bigman cried, "Sands of Mars, your man outweighs Lucky by fifty pounds and he's an expert with Agrav!"

Summers turned on him in mock surprise. "No! I never thought of that. What a shame!" There was laughter from the men. "On your way, Starr. Get into the corridor, Armand. Drag him in if you have to."

"He won't have to," said Lucky. He turned and moved into the open space of the wide Agrav corridor. As his feet drifted out into empty air, his fingers caught gently at the wall, twisting him in a slow, turning motion that he stopped with another touch against the wall. He stood there in midair, facing the men.

There was some murmuring at Lucky's maneuver, and Armand nodded, speaking for the first time in a rolling appreciative bass. "Hey, mister, that's not bad."

Summers, lips suddenly set and with a frown newly creasing his forehead, struck Armand a sharp blow on the back. "Don't talk, you idiot! Get in after him and give it to him."

Armand moved forward slowly. He said, "Hey, Red, let's not make too much of this."

Summers' face contorted in fury. "Get in there! And you do what I said. I told you what he is. If we don't get rid of him, they'll be sending more." His words were a harsh whisper that didn't carry.

Armand stepped into the corridor and stood face to face with Lucky.

Lucky Starr waited in what was almost absence of mind. He was concentrating on the faint whiffs of emotion brought him by the V-frog. Some he could recognize without difficulty, both as to their nature and their owner. Red Summers was easiest to detect: fear and niggling hate mixed with an undertone of anxious triumph. Armand loosed a small leak of tension. Occasionally there were sharp pinpoints of excitement from one or another, and sometimes Lucky could identify the owner because it coincided with a happy shout or a threatening one. All of it had to be sorted out from the steady trickle of Bigman's anger, of course.

But now he was staring into Armand's small eyes and he was aware that the other was bobbing up and down, a few inches either way. Armand's hand fingered his chest control.

Lucky was instantly alert. The other was alternating the gravitational direction, moving the controls this way and that. Was he expecting to confuse Lucky?

Lucky was sharply aware that for all his experience with space he was inexperienced in the type of weight- lessness brought about by Agrav, for this was a weightlessness that wasn't absolute, as in space, but one that could be changed at will.

And suddenly Armand dropped as though he had stepped through a trap door-except that he dropped upward!

As Armand's large legs moved up past Lucky's head, they parted and came together as if to catch Lucky's head in a vise.

Automatically Lucky's head snapped back, but as it did so, his legs moved forward, his body swinging about its center of gravity, and for a moment, he was off balance and flailing helplessly. A roar of laughter arose from the watching men.

Lucky knew what was wrong. He should have dodged by gravity. If Armand moved up, Lucky should have adjusted controls to move up with him or to race down past him. And now it would take the pull of gravity to straighten him out. At gravity zero, he would tumble indefinitely.

But before bis fingers could touch his controls, Armand was past the top of his rise and was gathering speed downward. As he dropped past Lucky once more, his elbow caught Lucky a sharp jab in the hip. He dropped farther and his thick fingers clutched at Lucky's ankles, carrying him down, down. Armand pulled strongly downward and reached up to seize Lucky's shoulders. His harsh breath stirred Lucky's hair. He said, "You need a lot of training, mister."

Lucky brought up his own arms head-high and broke the other's hold sharply.

Lucky dialed gravity up and helped Ms upward movement by bringing his foot sharply down on the other's shoulder, accelerating Ms own pace and slowing the other's. To his own senses it now seemed that he was falling head downward and there was a tenseness about that sensation that seemed to be slowing his reactions. Or was it his Agrav controls which were somewhat sluggish? He tested them and lacked the experience to be certain, yet felt that they were.

Armand was on him now, bellowing, thrusting against him, attempting to use his own greater mass of body to maneuver Lucky hard against the wall.

Lucky wriggled his hand toward the controls in order to reverse the direction of gravity. He readied his knees for an upward thrust to coincide and lurch Armand out of position.

But it was Annand's field that shifted first, and it was Lucky who was lurched out of position.

Annand's feet shot backward now, striking the wall of the corridor as it was flashing by and angling the pair, by recoil, against the opposite wall. Lucky struck bruisingly and skidded along it some feet before his ankle caught one of the metal railings and his body swung away and into the open corridor.

Armand whispered hotly in Lucky's ear, "Had enough, mister? Just tell Red you'll leave. I don't want to hurt you bad."

Lucky shook his head. Strange, he thought, that Ar-mand's gravitational field had beaten his own to the shift. He had felt Armand's hand move to the controls and he was certain his own controls had moved first.

Twisting suddenly, Lucky placed his elbow sharply in the pit of Armand's stomach. Armand grunted, and in that split second Lucky got his legs between himself and the other's and straightened them. The two men flew apart and Lucky was free.

He shot away an instant before Armand returned, and then for the next few minutes Lucky concentrated only on staying away. He was learning the use of the controls and they were sluggish. It was only by skillful use of the footholds along the walls and lightning-like head-to-foot reversals that he managed to avoid Armand.

And then while he was drifting feather-fashion, allowing Armand to shoot past him, he turned his Agrav controls and found no response at all. There was no change in the gravitational field direction; no sudden sensation of accelerating one way or the other.

Instead, Armand was on him again, grunting, and Lucky found himself crashing with stunning force against the corridor wall.