No, that wouldn't work. There had to be a place where the air was getting sucked in and drawn back. And if the air blew in at the outside walls, then the intake would be ... in the corridors.

Bean got up and ran to the door of the game room. Sure enough, the corridor's ceiling was at least twenty centimeters lower than the ceiling inside the room. But no vents. Just light fixtures.

He stepped back into the room and looked up. All along the top of the wall that bordered on the corridor there was a narrow vent that looked more decorative than practical. The opening was about three centimeters. Not even Bean could fit through the intake system.

He ran back to the open vent and took off his shoes. No reason to get hung up because his feet were so much bigger than they needed to be.

He faced the vent and swung his feet down into the opening. Then he wriggled until his legs were entirely down the hole and his buttocks rested on the rim of the vent. His feet still hadn't found bottom. Not a good sign. What if the vent dropped straight down into the machinery?

He wriggled back out, then went in the other way. It was harder and more painful, but now his arms were more usable, giving him a good grip on the floor as he slid chest-deep into the hole.

His feet touched bottom.

Using his toes, he probed. Yes, the ductwork ran to the left and the right, along the outside wall of the room. And the opening was tall enough that he could slide down into it, then wriggle – always on his side – along from room to room.

That was all he needed to know at present. He gave a little jump so his anus reached farther out onto the floor, meaning to use friction to let him pull himself up. Instead, he just slid back down into the vent.

Oh, this was excellent. Someone would come looking for him, eventually, or he'd be found by the next batch of kids who came in to play games, but he did not want to be found like this. More to the point, the ductwork would only give him an alternate route through the station if he could climb out of the vents. He had a mental image of somebody opening a vent and seeing his skull looking out at them, his dead body completely dried up in the warm wind of the air ducts where he starved to death or died of thirst trying to get out of the vents.

As long as he was just standing there, though, he might as well find out if he could cover the vent opening from the inside.

He reached over and, with difficulty, got a finger on the screen and was able to pull it toward him. Once he got a hand solidly on it, it wasn't hard at all to get it over the opening. He could even pull it in, tightly enough that it probably wouldn't be noticeably different to casual observers on the other side. With the vent closed, though, he had to keep his head turned to one side. There wasn't room enough for him to turn it. So once he got in the duct system, his head would either stay turned to the left or to the right. Great.

He pushed the vent back out, but carefully, so that it didn't fall to the floor. Now it was time to climb out in earnest.

After a couple more failures, he finally realized that the screen was exactly the tool he needed. Laying it down on the floor in front of the vent, he hooked his fingers under the far end. Pulling back on the screen provided him with the leverage to lift his body far enough to get his chest over the rim of the vent opening. It hurt, to hang the weight of his body on such a sharp edge, but now he could get up on his elbows and then on his hands, lifting his whole body up through the opening and back into the room.

He thought carefully through the sequence of muscles he had used and then thought about the equipment in the gym. Yes, he could strengthen those muscles.

He put the vent screen back into place. Then he pulled up his shirt and looked at the red marks on his skin where the rim of the vent opening had scraped him mercilessly. There was some blood. Interesting. How would he explain it, if anyone asked? He'd have to see if he could reinjure the same spot by climbing around on the bunks later.

He jogged out of the game room and down the corridor to the nearest pole, then dropped to the mess hall level. All the way, he wondered why he had felt such urgency about getting into the ducts. Whenever he got like that in the past, doing some task without knowing why it even mattered, it had turned out that there was a danger that he had sensed but that hadn't yet risen to his conscious mind. What was the danger here?

Then he realized – in Rotterdam, out on the street, he had always made sure he knew a back way out of everything, an alternate path to get from one place to another. If he was running from someone, he never dodged into a cul-de-sac to hide unless he knew another way out. In truth, he never really hid at all – he evaded pursuit by keeping on the move, always. No matter how awful the danger following him might be, he could not hold still. It felt terrible to be cornered. It hurt.

It hurt and was wet and cold and he was hungry and there wasn't enough air to breathe and people walked by and if they just lifted the lid they would find him and he had no way to run if they did that, he just had to sit there waiting for them to pass without noticing him. If they used the toilet and flushed it, the equipment wouldn't work right because the whole weight of his body was pressing down on the float. A lot of the water had spilled out of the tank when he climbed in. They'd notice something was wrong and they'd find him.

It was the worst experience of his life, and he couldn't stand the idea of ever hiding like that again. It wasn't the small space that bothered him, or that it was wet, or that he was hungry or alone. It was the fact that the only way out was into the arms of his pursuers.

Now that he understood that about himself, he could relax. He hadn't found the ductwork because he sensed some danger that hadn't yet risen to his conscious mind. He found the ductwork because he remembered how bad it felt to hide in the toilet tank as a toddler. So whatever danger there might be, he hadn't sensed it yet. It was just a childhood memory coming to the surface. Sister Carlotta had told him that a lot of human behavior was really acting out our responses to dangers long past. It hadn't sounded sensible to Bean at the time, but he didn't argue, and now he could see that she was right.

And how could he know there would never be a time when that narrow, dangerous highway through the ductwork might not be exactly the route he needed to save his life?

He never did palm the wall to light up green-brown-green. He knew exactly where his barracks was. How could he not? He had been there before, and knew every step between the barracks and every other place he had visited in the station.

And when he got there, Dimak had not yet returned with the slow eaters. His whole exploration hadn't taken more than twenty minutes, including his conversation with Petra and watching two quick computer games during the class break.

He awkwardly hoisted himself up from the lower bunk, dangling for a while from his chest on the rim of the second bunk. Long enough that it hurt in pretty much the same spot he had injured climbing out of the vent. "What are you doing?" asked one of the launchies near him.

Since the truth wouldn't be understood, he answered truthfully. "Injuring my chest," he said.

"I'm trying to sleep," said the other boy. "You're supposed to sleep, too."

"Naptime," said another boy. "I feel like I'm some stupid four-year-old."

Bean wondered vaguely what these boys' lives had been like, when taking a nap made them think of being four years old.

Sister Carlotta stood beside Pablo de Noches, looking at the toilet tank. "Old-fashioned kind," said Pablo. "Norteamericano. Very popular for a while back when the Netherlands first became international."