"Attention! Attention! This is a general alert!" Tom Corbett's voice was hollow as he spoke over a solar-wide audiocast. "Wanted! Space Cadet Roger Manning. Five feet, eleven inches tall, one hundred sixty-five pounds. Blue eyes. Blond hair. Last seen wearing dress blues. Cadet Manning broke confinement to quarters on Venus space station and is believed to be heading back to Earth. He is wanted in connection with the crash of the space freighter Annie Jones and the death of two spacemen. All information regarding the whereabouts of Manning should be forwarded to Captain Isaiah M. Patrick, Senior Security Officer, Solar Guard, Space Academy, Earth. This alert is to be transmitted to all local authorities."

Tom snapped the switch off and silently watched the glowing audio tubes darken. He turned to one side and saw Astro. The big Venusian was seated on a desk, slumped over, his head held in his massive hands.

"You know," said Astro slowly, "I could take that guy Manning and break him in two for running out!"

Tom didn't answer. When they had discovered that Roger was missing it had been a terrific blow. Unaware that Roger, in his confused state of mind, had been an easy victim to Loring and Mason's trickery and had innocently walked into their trap, the two cadets felt that his escape was a breach of trust. Roger had given his spaceman's word that he would confine himself to his quarters. Roger had broken that trust, and now the fact was being flashed around the entire solar system; Roger Manning was an escaped criminal!

"There's nothing we can do now," said Tom. "The whole universe knows it. He's finished! Washed up! The only thing that could save him now would be absolute clearance by the investigation. But since he's run out, I guess it must be the other way around. He was afraid he was going to get caught." Tom's voice was cold and bitter. "And we can't blame anyone but—"

"But Manning!" barked a voice behind them. Astro jumped up and snapped to attention. Tom turned to see Major Connel stride into the room. It was at Connel's insistence that Tom had been ordered to broadcast the alert for Roger.

"That's the last time I ever want to hear any sympathy for a man who broke his word!" snarled Connel.

"I have something I'd like to say to the major," said Astro in a deliberate voice, "as man to man!"

Even at attention, Tom jerked his head involuntarily to look at Astro. Connel's eyes narrowed. "Here it comes," he thought. "Well, I've handled rebellion of this sort before." He stepped close to Astro. So close in fact that the black and gold of his uniform brushed the massive chest of the cadet from Venus.

"You have permission to speak, man to man!" snapped Connel.

Astro paused for a moment. Then he relaxed and brought his eyes down to the level of the major.

"I am a human being, sir," said Astro in the deepest voice Tom had ever heard. It was strong and full of emotion, yet controlled. "And as long as I am a human being, I shall consider Roger Manning one of the finest men I'll ever know."

"Are you finished?" snapped Connel.

"No, sir, I'm not," said Astro. "I speak in defense of the man, the spaceman, not the uniform, or the trust he betrayed. And I respectfully request of the major that if his feelings for Cadet Manning are so violent that he finds it difficult to control them, that he make a special effort to control them"—Astro paused and stuck out his chin—"in my presence!"

Connel stepped back. "And if I don't?" he shouted.

"Then I shall ask for a transfer from your command, sir, and if that is not granted, then I shall resign from the Academy."

"And?" asked Connel.

"And, sir—" Astro stumbled.

"And what, Cadet Astro?" roared Connel.

"I have nothing more to say, sir," said Astro.

Tom, who had at first had to control an impulse to laugh at the strange seriousness of Astro's manner and tone, now found it equally difficult to hold back the tears that were welling up in his eyes.

Connel was not going to let the incident stand there. He had secretly hoped that such a situation would present itself, because he wanted to see what material the Polaris unit was made of. And he was secretly satisfied. Any cadet who would offer to resign from the Academy in defense of his unit-mate was a true spaceman. Connel wasn't going to allow Astro or Tom to resign over some foolish trick of Roger's, but, at the same time, he couldn't allow them to take too many liberties with discipline. Connel turned to Tom.

"I suppose you feel the same way, Corbett?" he asked.

"I do, sir," said Tom.

"Of course you know I could make your lives miserable now," he threatened.

"We are aware of that, sir," said Tom quietly.

"Very well, Cadets Corbett and Astro. I shall comply with your request. Not because of your request but out of respect for your feelings as spacemen. I wouldn't have thought much of you if you hadn't come out in defense of Manning. And just for your own sake, Astro," said Connel, stepping back in front of the big cadet, "never ask to talk to a Solar Guard officer man to man again. As long as you're still a member of the Cadet Corps such disrespect will not be tolerated. Another man, who might not have understood your feelings, could have used your desire for fair play as a means of trapping you into one of the worst offenses in the Spaceman's Code—striking a Solar Guard officer!"

"Yes, sir," mumbled Astro. "Thank you, sir."

"Report aboard the Polaris"—Connel glanced at his watch—"in fifteen minutes. I'm going to put you through your paces on hyperdrive and the operation of the transmitter."

"Then we're still going to make the trip to Tara, sir?" asked Tom.

"We certainly are, Corbett," replied Connel. "In two hours another cadet is arriving from the Academy to replace Roger. His name's Alfie Higgins. Perhaps you know him."

Tom smiled. "Yes, sir, we know him," he replied. "Cadet Higgins is a friend of mine. He carries the nickname of 'The Brain.' Has the highest I.Q. in the Academy."

"Good. I'm glad you know him, because this is going to be a rough trip. We got off to a bad start, but it's all over now. So forget it. And before I go, I want you to know this. In my personal opinion, Manning had nothing to do with the crash. I think the whole trouble was caused on the ship. I have nothing to back up my opinion, except my feelings. But feelings can go a long way in making a man innocent until proved guilty. Unit dis-missed!"

Alfie Higgins listened attentively to the story of the crash and Roger's disappearance as Tom, and then Astro, described the situation in detail.

"It is a pity, of course, but Manning was always the impulsive type. Not very definite in his attitude and emotionally unstable," commented Alfie when the story was finished.

"Lay off that talk, you overstuffed brain!" growled Astro. "In this outfit, Roger is just away on vacation!"

"Yes—yes, of course!" said Alfie quickly. It wasn't wise to get off on the wrong foot in a new unit, especially when one was trying to fill the shoes of a cadet, who, Alfie had to admit, had everything. Alfie Higgins' mother didn't raise any stupid children, he said to himself. He was too happy being a member of the Polaris unit, the hottest crew at the Academy, to allow anything to interfere with his success.

"I've heard a great deal about hyperdrive," he said quickly, changing the subject. "I would appreciate it if you could describe the basis of this new feature in space travel so that I may have at least a surface familiarity with its operation and application."

Astro gulped and looked at Tom. "Might as well get used to that kind of chatter, Astro," said Tom, smiling. "Alfie can't talk any other way."

"Is there something wrong with the way I speak?" asked Alfie, wrinkling up his nose a little to see through the thick lenses of his glasses.

"You wanta know about hyperdrive?" growled Astro.

"To be sure, if you'd be so kind," said Alfie.

"Well, if you'll close your trap long enough, I'll tell you about it!"

Alfie sat back and waited, hands clasped around one knee.

"In the first place," began Astro, "hyperdrive was developed by Joan Dale back at the Academy. And it's so blasted simple, I get mad at myself for not thinking of it first!"

"Uhhh," snorted Alfie. "I respect your great talent on the power deck, Astro, but I would hardly compare myself with Dale!"

"Shut up!" barked Astro. "You'll see how simple it is! Hyperdrive is based on the idea that the thrust of the rockets acts in the exact same way on all the atoms inside the spaceship. So you can have as much thrust as you want and no one will feel a thing. Even if the ship were to accelerate a million times faster than the gravity of the Earth you wouldn't feel a thing, because all the atoms inside would be pushed along at the same time!" Astro sat back triumphantly.

"Ummmmh," commented Alfie. "That sounds all right as a principle, but will it work out in space?"

"Listen, you—you—" snorted Astro.

"Sure it will, Alfie," said Tom. "It's been tested before."

"Still room for improvement, though," commented Alfie.

"I'll improve your head," barked Astro, "if you don't close that big mouth! How do you like that, Tom? We get rid of one space-gassing Romeo and now we get one even worse!"

Astro's reference to Roger made Tom draw a quick breath. In the short while since Alfie's arrival and the week since Roger's disappearance there hadn't been time to forget their old unit-mate and get accustomed to a new personality. Astro sensed Tom's feelings and irritably banged one hamlike fist into the other. Alfie was O.K., thought the big Venusian, but by the craters of Luna, he wasn't Roger.

"Attention—attention!" The intercom crackled into life. "Polaris unit—by order of Major Connel—stand by to blast off immediately. This is first warning! Pack your gear and stand by to blast off immediately."

Tom, Astro, and Alfie got up, and with the image of Roger fresh in their minds, made their way to the landing-port deck where the great gleaming spaceship was slung on magnetic cradles. They were met at the hatch by Major Connel.

"All right," he said, "we leave all thoughts of Manning right here on the station. I know it's tough, but we've got a still tougher job to do. This is to be a scientific expedition and we'll need every ounce of energy and intelligence we have—collectively—to make a success of this mission. Cadet Corbett!"

"Yes, sir," replied Tom.

"Stand by to blast off in five minutes!"