Barrent had no more time to listen. He was standing in a long, narrow corridor. He turned to the right and raced toward the bow of the ship. Far behind him, he could hear the heavy marching tread of the guards. Now, he thought, the information he had been given about the ship had better be right, or the expedition was finished before it began. He sprinted past rows of empty cells, and came to a door marked GUARD ASSEMBLY ROOM. A lighted green bulb above the door showed that the air system was on. He went by it, and came to another door. Barrent tried it now, and found it unlocked. Within was a room stacked high with spare engine parts. He entered and closed the door. The guards marched down the corridor. Barrent could hear them talking as they entered the assembly room. "What do you think started those explosions?" "Who knows? Those prisoners are crazy, anyhow." "They'd blow up the whole planet, if they could." "Good riddance." "Well, it didn't cause any damage. There was an explosion like that about fifteen years ago. Remember?" "I wasn't here then." "Well, it was worse than this. Two guards were killed, and maybe a hundred prisoners." "What started it?" "Don't know. These Omegans just enjoy blowing things up." "Next thing you know, they'll be trying to blow _us_ up." "Not a chance. Not with the guardships up there." "You think so? Well, I'll be glad to get back to the checkpoint." "You said it. Be good to get off this ship and live a little." "It isn't a bad life at the checkpoint, but I'd rather go back to Earth." "Well, you can't have everything." The last of the guards entered the assembly room and dogged the door shut. Barrent waited. After a while, he felt the ship vibrate. It was beginning its departure. He had learned some valuable information. Apparently all or most of the guards got off at the checkpoint. Did that mean that another detachment of guards got on? Probably. And a checkpoint implied that the ship was searched for escaped prisoners. It was probably only a perfunctory search, since no prisoner had escaped in the history of Omega. Still, he would have to figure out a way of avoiding it. But he would face that when the time came. Now he felt the vibration cease, and he knew that the ship had left the surface of Omega. He was aboard, unobserved, and the ship was on its way to Earth. So far, everything had gone according to plan. * * * * * For the next few hours, Barrent stayed in the storage room. He was feeling very tired, and his joints had begun to ache. The air in the small room had a sour, exhausted smell. Forcing himself to his feet, Barrent walked to the air vent and put his hand over it. No air was coming through. He took a small gauge out of his pocket. The oxygen content of the room was falling rapidly.